# Gravity G29 rear cargo rack



## vassock (Jun 29, 2009)

So I have the G29 now and it looks like it does have those two bolts at the rear tubes going to the wheel. I thought I'd start a new thread on this issue specifically since I now can get specific info about the bike. I saw this on sale:

Amazon.com : Axiom Journey Uni-Fit MK 2 Rear Rack : Bike Racks : Sports & Outdoors

and was wondering how exactly does it get attached to the bike?


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## Rustedthrough (Aug 19, 2014)

Like this. The rack can be mounted at the axles, but it doesn't have enough clearance over 29er tires.


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## vassock (Jun 29, 2009)

Really? Description says: Fits 26", 27", 28", 700C, 650B, 29"

So if that doesn't fit, what rack do I get?

How did you attach the front part of it to the bike? The one on Amazon looks like there is just one part at the front, whereas it looks like you attached two to your bike.


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## Rustedthrough (Aug 19, 2014)

If you have braze-ons above your axle on the seat stays, and at the top of the seat stays or one at the bridge, you are in good shape.

It does fit a 29er if it is mounted to the braze- ons, not if it is skewer/ axle mounted. If you look back at your earlier postings, you will see the skewer mounted rack that I suggested, and some suggestions from others.

The Axiom racks come with a single stainless strap, and a pair of dark tubing straps like the ones in my photo. You have both options with these racks.

Can you post a close up photo of your Gravity's rear axle region and the area just below the seat post clamp? The stock photos don't give enough detail to be helpful here.


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## Rustedthrough (Aug 19, 2014)

To be clear, the Axiom Journey rack will fit a 29er if it is mounted like the rack on my Bosanova. It will not fit, or at least not fit well, if it is mounted at the skewers/ axles/ quick releases, unless you have fairly small tires. Fitting the front of the rack to the seatpost clamp, bridge, or upper braze- ons on the seat stays should not be a problem.

These photos are probably not very helpful. This 29er does not have the lower braze-ons for a rack. So I mounted a Blackburn rack designed to mount at the quick releases, using a single stainless strap (under the tupperware fender) for the front mount. I can take some photos from the other side tomorrow if you are unsure about the mounting systems.


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## newfangled (Sep 13, 2010)

vassock said:


> Really? Description says: Fits 26", 27", 28", 700C, 650B, 29"


One of the amazon reviews for the Unifit Mk3 has a photo where the guy modified the "feet" by drilling an additional hole, which let him rotate the whole thing up to fit his 29er: http://www.amazon.com/review/R3TFU9...009VU3RAU&nodeID=3375251&store=sporting-goods









But even with that, if you're using the fancy mounting struts (instead of the single sheetmetal stay) you might need to flip them upside-down like I did here:



__
https://flic.kr/p/r2hoSa

But yeah, even their "29er" streamliner doesn't really fit a 29er very well. It's pretty dumb.

I realize you're not using the qr, but even the typical rack mount only raises it about an inch.


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## vassock (Jun 29, 2009)

Rustedthrough said:


> If you have braze-ons above your axle on the seat stays, and at the top of the seat stays or one at the bridge, you are in good shape.
> 
> It does fit a 29er if it is mounted to the braze- ons, not if it is skewer/ axle mounted. If you look back at your earlier postings, you will see the skewer mounted rack that I suggested, and some suggestions from others.
> 
> ...


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## Rustedthrough (Aug 19, 2014)

Nice color Vassock. It looks like you have both options for the upper mounts, but, you will need to get creative at the rear end.

The simplest solution is to go with a QR mounted rack. Another cheap possibility is to mount a standard disc brake rack with "p- clamps" on the seat stays. Newfangled has some really good photos of the p- clamp system in the thread "best rear rack without braze- ons." I'm sure there are other good photos around here.

I'll post a photo or two of my Unit with the Blackburn QR mounted rack in just a minute or two.


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## Rustedthrough (Aug 19, 2014)

Sorry Vassock, I am experiencing technical difficulties between the phone, laptop and forum. It might be tomorrow before I can get the pics up.

Looking again at your photos, I wonder if you have a through axle. The Blackburn rack comes with a replacement axle with quick release. It may not be a solution for your bike. If you cannot remove the axle from your wheel by simply removing the nuts on either side, this particular rack will not fit.

If this is the case, either modifying the Axiom rack as in the photo above, or mounting it to p- clamps on the seta stays might be the best options.


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## Rustedthrough (Aug 19, 2014)

Files finally transferred. The two of the blue bike are the Blackburn QR mounted rack. The Black road-ish bike is the Axiom rack mounted as intended on the braze- ons.


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## newfangled (Sep 13, 2010)

It's so weird that a frame has the upper rack brazeons, but nothing lower down. I don't think those upper ones serve any purpose without lower ones too?

So here are my p-clamp/hoseclamp photos that rustedthrough mentioned:



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https://flic.kr/p/bp1MbW



__
https://flic.kr/p/bp1MvW

Alternatively you could find a bike co-op, and replace the solid rear axle with a quick release, and then you'd be able to use the QR racks.


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## vassock (Jun 29, 2009)

newfangled said:


> It's so weird that a frame has the upper rack brazeons, but nothing lower down. I don't think those upper ones serve any purpose without lower ones too?
> 
> So here are my p-clamp/hoseclamp photos that rustedthrough mentioned:
> 
> ...


I can't tell what I'm looking at due to my lack of knowledge in the terms and the dirt in the photo. Can you be more specific regarding what rack I need to buy? Do you need more photos to look for other mounting points?


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## Rustedthrough (Aug 19, 2014)

Newfangled has mounted a standard rack to his bike using "P" clamps to create mounting points. 

These can be had for a few dollars each from any good hardware store, in a few different sizes. Since the Gravity has the upper but not the lower mounting points for a rack, a normal disc brake compatible rack mounted to this type of clamp is likely the cheapest option.


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## Rustedthrough (Aug 19, 2014)

You are looking for something like this:
5/8 in. Rubber Insulated Metal Clamps (2-Pack)-67792 - The Home Depot

The clamp is mounted to the same tubing on the bike as the small bolts in your photo, but just above or below the brake hardware, the rack is bolted to the clamp rather than directly to the frame.


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## Rustedthrough (Aug 19, 2014)

I prefer the Axiom racks. The little boots/ feet at the bottom of the rack give more heel clearance between the pedal and the pannier. This system would let you use the Axiom rack that started the conversation.

The clamp would be mounted on your Gravity at about the same place as the bolts holding the feet to the frame of my black bike in the photo above. You should measure the seat stays first, as these clamps are available in a range of sizes. I would guess from your pics that you will need clamps around 5/8s inch to 3/4". You may also need to buy some new bolts and nuts for this operation.


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## vassock (Jun 29, 2009)

Rustedthrough said:


> I prefer the Axiom racks. The little boots/ feet at the bottom of the rack give more heel clearance between the pedal and the pannier. This system would let you use the Axiom rack that started the conversation.
> 
> The clamp would be mounted on your Gravity at about the same place as the bolts holding the feet to the frame of my black bike in the photo above. You should measure the seat stays first, as these clamps are available in a range of sizes. I would guess from your pics that you will need clamps around 5/8s inch to 3/4". You may also need to buy some new bolts and nuts for this operation.


Ah, ok. So the rack attaches to the bolt holes near the seatpost on top, and to the holes created by the c-clamps (attached to the frame beams going to the wheel) on the bottom. So I need 2 of those c-clamps and what rack product?


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## Rustedthrough (Aug 19, 2014)

The Axiom Journey Unifit should work nicely with the clamps. The 29er version Streamliner from Axiom has a little more clearance if you can find it.

You could mount a slightly less expensive rack to the new mounts (clamps), but you might have some issues with your heel striking the pannier.

Do you plan to use side mounted panniers or boxes, or just top mounted bags/ boxes on the rack?


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## Rustedthrough (Aug 19, 2014)

If you are only using top mounted bags or boxes, a cheaper rack like this would work.

http://www.amazon.com/Ibera-Bicycle...qid=1426220420&sr=8-2&keywords=bike+rack+29er

If you are even considering using side mount carriers, then Axiom and similar racks are worth the extra money.


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## vassock (Jun 29, 2009)

Rustedthrough said:


> If you are only using top mounted bags or boxes, a cheaper rack like this would work.
> 
> http://www.amazon.com/Ibera-Bicycle...qid=1426220420&sr=8-2&keywords=bike+rack+29er
> 
> If you are even considering using side mount carriers, then Axiom and similar racks are worth the extra money.


I want to keep my options open. Here is what I found:

http://www.amazon.com/Axiom-Journey-Uni-Fit-Cycle-Black/dp/B009VU3RAU

It's a bit more money, but I think it's better to get the right thing the first time. Here is what a buyer had to say about it:

_
I have a 29er with no lower eyelets and needed to mount it to the QR axle skewer. I'd previously been using an Axiom Streamliner DLX Disc, but that's not advertised as working on 29ers and it left very little clearance between the rack and tire. Hoping to get enough room to add a fender, I tried the Uni-Fit. However, using the longest supplied adapter legs in the 29" position, the rack just barely cleared the tire (I think there was even less clearance than the Streamliner). I was able to drill new holes in the adapters to increase the height another 1/2" or so, but Axiom should have thought of this.

The rack seems well made and should hold up. The rack itself is pretty light, although the center-caliper-mount adapter is a pretty hefty piece of metal (much longer/wider/thicker than the adapter from the Streamliner DLX). *This isn't an issue if you use the upper seatstay eyelet adapters*._

I believe the two bolts that are in the pics are those "eyelets?" So will this item work with my 29er and with:
Ideal 5 8" Rubber Insulated Clamps 2pcs USA 772856L | eBay

? Are you sure the size will work?


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## Rustedthrough (Aug 19, 2014)

The Amazon reviewer had the same problem I had when trying to mount the rack to the axle rather than to rack mounting braze- ons. If you are using the clamps to create mounting points, I am sure it will fit. 

I'm not sure what he/ she means about the "upper seat stay eyelet adapters," but your Gravity is drilled to accept either the single stainless strap, or the tubular stays. You have your choice there. Expect to bend them slightly whichever one you choose.

For the clamps, a little smaller than the tubing diameter is better than a little larger (if your seat stay tubing is 9/16" as near to the axle as you can get, a 1/2" clamp would be better than a 5/8" clamp.)


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## Rustedthrough (Aug 19, 2014)

"Eyelet adapters." Looked again at the amazon review and pics. I'm fairly certain that the reviewer was commenting on the beefiness of the stainless strap versus the tubular stays you see mounted in my photo or in Newfangled's photos.

Redrilling the mounting holes on the rack's "feet" is an option, as shown in the second reviewer photo. You might mount the rack first with the clamps and reserve the drilling option for later.

Have you got a few miles on the bike yet? Is it as fun as it looks?


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## vassock (Jun 29, 2009)

Rustedthrough said:


> "Eyelet adapters." Looked again at the amazon review and pics. I'm fairly certain that the reviewer was commenting on the beefiness of the stainless strap versus the tubular stays you see mounted in my photo or in Newfangled's photos.
> 
> Redrilling the mounting holes on the rack's "feet" is an option, as shown in the second reviewer photo. You might mount the rack first with the clamps and reserve the drilling option for later.
> 
> Have you got a few miles on the bike yet? Is it as fun as it looks?


I have no idea how to measure the tubes.

Yes I got some miles on it. It's nice, but hits the hands a bit hard when I hit a bump. No suspension and all.


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## Rustedthrough (Aug 19, 2014)

Do you have a Crescent wrench and a tape measure? Or, some masking tape, a razor blade, and a tape measure or ruler, and a calculator?

As for the hands, you can get softer grips that will take some of the sting out. I replaced my stock grips with ESI Chunky grips and found that the larger diameter seems to reduce my tendency to grasp too tightly as well as pad the hands better. There are several grip options available for under $30.


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## newfangled (Sep 13, 2010)

If you're going to use clamps it's a good idea to wrap some electrical to protect the paint. I just sold my Kona, and after 4 years the paint under the tape was still in great shape.

For my kona 1/2" clamps were way too small, and 3/4" were a tiny bit too large. But with a couple of layers of tape they were good. So probably either 5/8 or 3/4 would be workable.

And riding rigid does take a could of rides to get used to, but now it's all I ride. What tire pressure are you running upfront? I'm usually below 25psi (or even 20), and that can help.


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## vassock (Jun 29, 2009)

newfangled said:


> if you're going to use clamps it's a good idea to wrap some electrical to protect the paint. I just sold my kona, and after 4 years the paint under the tape was still in great shape.
> 
> For my kona 1/2" clamps were way too small, and 3/4" were a tiny bit too large. But with a couple of layers of tape they were good. So probably either 5/8 or 3/4 would be workable.
> 
> And riding rigid does take a could of rides to get used to, but now it's all i ride. What tire pressure are you running upfront? I'm usually below 25psi (or even 20), and that can help.


60 psi.


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## vassock (Jun 29, 2009)

Okay, so just confirming:


Details about Ideal 5/8" Rubber Insulated Clamps 2pcs. USA 772856L
and
Axiom Mk Journey Uni-Fit Cycle Rear Rack, Black

I assume this should fit? I will buy it upon confirmation.


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## Rustedthrough (Aug 19, 2014)

It will fit.


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## newfangled (Sep 13, 2010)

vassock said:


> 60 psi.


Well there's your problem.


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## vassock (Jun 29, 2009)

newfangled said:


> Well there's your problem.


I read lower pressures could increase the chance of popping the tire. Plus I am on the heavier side. Can high pressures damage the wheel or anything else on the bike?


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## Rustedthrough (Aug 19, 2014)

High pressure can break the rim, pressure too low can cause pinch flats. Too little pressure increases rolling resistance, too much makes the ride harsh. Stay within the range listed on the side of the tire, typically something like 30- 55 psi.

You can run higher pressure in the rear tire to reduce rolling resistance, and lower front tire pressure to improve the ride. Much more of your weight is carried by the rear tire than the front. Try running the front at 30 psi and the rear at 45 for a day, then try 25 and 40. If you have the stock knobby tires on the Gravity, they are probably not designed for anything over 45 psi.

When I started riding again, on a rigid 26" mtb, I weighed 230 lbs and had little patience for rolling resistance. I got a set of semi slick tires and ran the pressure to the limit, had numb hands and other parts for a few weeks, and then eased back on the inflation. Play with your tire pressures, it is the one thing you can change for free on a daily basis.


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## newfangled (Sep 13, 2010)

Most of your weight will be on your back tire, so no matter how heavy you are you should be able to run your front tire with a lower pressure than the back. Especially with rigid, having that extra little bit of cush upfront is helpful.

The biggest thing to worry about with low pressures is that it increases the risk of pinch-flatting, or striking the rim on curbs. But that is mostly about the back tire where all the weight is. And at 60psi you're nowhere near that.

It looks like your bike comes with 2.1" tires, so I'd say try 30psi front and 40psi back? Or 35psi front and 50psi back?

Right now at 60psi the tires are probably rockhard. When you soften them up a bit they'll enter the basketball phase, which also isn't great because then they just bounce off of everything. The front is where it's really important, and you want to get it down to the point where it's actually providing a bit of "suspension".

Just for comparison, I'm probably around 190lb (haven't checked in awhile), run tires between 2.25" to 2.4" wide, and usually run 20psi upfront and 25psi in back.

_edited to add: oops, rustedthrough already said all of that._


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## Rustedthrough (Aug 19, 2014)

^Not sure I said it all, thanks for backing it up. 

Vassock, all that green over Newfangled's dog has nothing to do with St. Pats. 20 psi front, 25 rear seems too low for pavement (for me) but the concept is spot on. Play with it a bit, air is cheap.

Once you get the tire pressure sorted out, play with the way you approach curbs and potholes. I created no end of trouble for myself by gripping the bars tightly and bashing into things, or failing to lift over them. The larger grips have probably helped more by forcing me into a more relaxed (still controlled) grasp than they have by cushioning the blow.


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## newfangled (Sep 13, 2010)

Rustedthrough said:


> 20 psi front, 25 rear seems too low for pavement (for me) but the concept is spot on.


That's a good point. I was only giving it was example of what I run without any problems. But my bikes see pavement and dirt, and on dirt low pressures are good to give traction and conform to the trail.

30psi upfront and whatever on the back would be a good place to start.


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## vassock (Jun 29, 2009)

newfangled said:


> That's a good point. I was only giving it was example of what I run without any problems. But my bikes see pavement and dirt, and on dirt low pressures are good to give traction and conform to the trail.
> 
> 30psi upfront and whatever on the back would be a good place to start.


I think the max PSI on those is listed at 65 PSI. I checked before filling it.

Hawley

You can get the specs for the tires from the website that sells Gravity G29 (bikes direct).


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## Rustedthrough (Aug 19, 2014)

That is certainly possible. If you like the way the Gravity rolls with 60 psi, try dropping the front tire pressure to about 45 psi and leave the rear pressure alone. Changing the front tire pressure won't change rolling resistance much, but it will soften the bumps.


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## vassock (Jun 29, 2009)

Looks like the circumference of the lower bar on the frame is just under 2.5 inches. Perhaps I need a different size c-clamp.


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## Rustedthrough (Aug 19, 2014)

If I've got my math right, that gives you 13/ 16 tubing. 3/4" clamp should work well, or 7/8" with a few more wraps of electrical tape. The 5/8" clamp might work with the foot of the rack placed between the clamp ends.


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## vassock (Jun 29, 2009)

Rustedthrough said:


> If I've got my math right, that gives you 13/ 16 tubing. 3/4" clamp should work well, or 7/8" with a few more wraps of electrical tape. The 5/8" clamp might work with the foot of the rack placed between the clamp ends.


I'll get the 7/8" one. I can put a layer of silicone where the clamp will go. It turns to rubber when it cures.

Do I need any bolts/nuts to go with that?


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## Rustedthrough (Aug 19, 2014)

13/16" seems large for the seat stays. It might be worth measuring one more time. If it measures the same, silicone or strips of old inner tube, or lots of electrical tape should do the trick with a 7/8" clamp. Circumference divided by 3.14 will get you very close to the clamp size in decimal, multiply that by 16 to get it in 16th of an inch.


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## vassock (Jun 29, 2009)

What is a lower end pannier compatible with this and reliably stays on? I prefer something that is a bit higher up so it does not touch the wheel.


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## Rustedthrough (Aug 19, 2014)

Do you plan to leave the pannier on most of the time, or take it off when you reach your destination? How important is it that the pannier be waterproof?

Axiom (the same company that made the rack) makes a wide selection of good panniers for a fair price. The Appalachian is well worth a look if you plan to leave them on the bike. Donkey Boxx is the white plastic pannier on my blue bike, $28 from the manufacturer when I got it and dead simple held on with zip ties.

If you want to take your pannier with you, Thule has a slick mounting system and you can get previous year models on Amazon for a reasonable price (current year stock is pricey). 

You can mount any good pannier you can find to the Axiom rack, including Wald and other brands of folding steel baskets. What you need to carry, how often you expect to remove the bag from the bike, and how weather proof the bag needs to be will make a big difference in what makes a good pannier for you.


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## Rustedthrough (Aug 19, 2014)

I got this set when I started commuting and shopping by bike. Seems like it was cheaper then. No frills, no bells, no whistles, not quite waterproof, but a very practical set of bags to haul groceries and school supplies.

Bell Rucksack 800 Shopping Pannier Bag - Walmart.com

Axiom's Appalachian is very similar, though I expect it has better mounting straps.


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## Rustedthrough (Aug 19, 2014)

Any progress on the rack Vassock?


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## vassock (Jun 29, 2009)

Rustedthrough said:


> Any progress on the rack Vassock?


I plan on buying the last part I need, the c-clamps, tomorrow.


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## Rustedthrough (Aug 19, 2014)

Holler out if you have any questions when putting it together.


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## otherground (Mar 16, 2015)

*Axiom journey mounting plates..........*

Got that rack because of the plates. I was doing some research because I just got a Diamondback overdrive which has no eyelets and a funky curved lip over the rear dropout. Before ordering the rack I got me the Bontrager dropout rack adapter which was half the price of the Tubus version. it took a while but i was able to finally get the rack on the bike.


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## Rustedthrough (Aug 19, 2014)

^ Nice adaptation. Did you drill new holes in the plates/ feet/ what ever they are, or just use an unusual configuration of the existing holes?


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## otherground (Mar 16, 2015)

*Thanks!*



Rustedthrough said:


> ^ Nice adaptation. Did you drill new holes in the plates/ feet/ what ever they are, or just use an unusual configuration of the existing holes?


I didn't have to drill anything, it was just by luck that I had 2 holes match up on the plate and rack in a position that worked. I couldn't have done it without those bontrager adapters though.


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## Rustedthrough (Aug 19, 2014)

^ Sweet. I might have to track down a set of those for my Unit. Do you have a part number or name close at hand?


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## otherground (Mar 16, 2015)

*go to the trekstore website*



Rustedthrough said:


> ^ Sweet. I might have to track down a set of those for my Unit. Do you have a part number or name close at hand?


Bontrager BackRack Parts - Racks - Accessories -Trek Store

and make these selections after searching:









you can hit the more views button if you want to check out all the stuff they have for racks


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## Rustedthrough (Aug 19, 2014)

Went there, no good photos. If I am following, they are these:

Bontrager Back Rack Light Weight Dropout Plates Kit | Evans Cycles

At about $8 for a set from Trek. Did you need a longer skewer to mount them?


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## newfangled (Sep 13, 2010)

That's a nicely macguyvered setup.

But when I used p-clamps for the upper mounts, I found the whole thing was a little floppier than I would have liked. I switched to a seatpost clamp with rack mounts which felt a lot more solid. Just something to think about.


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## otherground (Mar 16, 2015)

Rustedthrough said:


> Went there, no good photos. If I am following, they are these:
> 
> Bontrager Back Rack Light Weight Dropout Plates Kit | Evans Cycles
> 
> At about $8 for a set from Trek. Did you need a longer skewer to mount them?


That's them. Stock skewer works fine for me.



newfangled said:


> That's a nicely macguyvered setup.
> 
> But when I used p-clamps for the upper mounts, I found the whole thing was a little floppier than I would have liked. I switched to a seatpost clamp with rack mounts which felt a lot more solid. Just something to think about.


Thanks!
I pounded on the rack a bit to make sure everything stayed in place so it looks like it'll hold. Because of the way the rack is positioned farther to the back i'd have to go and get longer arms to connect to the seat post adapter. Once i get a hold of some panniers i'll take it out loaded to the local park and hit this little rough section I know about. gotta test it before you use it real world.


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## Rustedthrough (Aug 19, 2014)

otherground, welcome to the commuter part of the forum. I should have said that earlier.

Are you sure you'd need longer arms for a seat post clamp mount? Looking at your photos it looks like you might gain a little by bringing the arms up, at least in fender clearance.


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## newfangled (Sep 13, 2010)

otherground said:


> Because of the way the rack is positioned farther to the back i'd have to go and get longer arms to connect to the seat post adapter.


Like rustedthrough says, based on the photo it looks like the distance to a seatclamp would be about the same if you did end up wanting to switch.

One other thing about the p-clamps - did you put electrical tape or anything underneath them to protect the frame? I used p-clamps with a beater frame, and they stripped the paint right off. But on my kona I used a layer or two of electrical tape, and the paint was in great shape years later.


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## vassock (Jun 29, 2009)

Well I finally got it working, mounting via 1" c-clamps (3/4 inch not available in the store) over a thick layer of cured silicone. No problems so far, except that the weight seems to be high up and makes the bike unwieldy when turning. Any leaning and it falls right down.


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## Rustedthrough (Aug 19, 2014)

Congratulations.

Does it seem to stay fixed, even after a fall? I'm afraid that the top- heavy aspect is the nature of the beast, unless you can load panniers low on the sides. 

Are you running with weight on top of the rack, or on the sides now?


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## vassock (Jun 29, 2009)

Rustedthrough said:


> Congratulations.
> 
> Does it seem to stay fixed, even after a fall? I'm afraid that the top- heavy aspect is the nature of the beast, unless you can load panniers low on the sides.
> 
> Are you running with weight on top of the rack, or on the sides now?


I have not actually dropped it yet. Just something I felt while riding and storing it. Any alternatives to securing the bottom pieces to the frame?


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## Rustedthrough (Aug 19, 2014)

If you mean alternatives to the p- clamps, take a look at the end of page 2 of this thread, and the top of this page.

If that's not what you mean, could you rephrase the question?


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## vassock (Jun 29, 2009)

Rustedthrough said:


> If you mean alternatives to the p- clamps, take a look at the end of page 2 of this thread, and the top of this page.
> 
> If that's not what you mean, could you rephrase the question?


How do those work? Do they just go between the main nut holding the wheel on at the rear dropout and the frame? How do I know if it's a compatible size hole for the bolt holding the wheel on?


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## Rustedthrough (Aug 19, 2014)

They work just like you said. QR/ Skewer diameter seems to be fairly standardized. You will likely have to mount the plates/ feet on the rack (not the Bontrager plates) in an unusual pattern like otherground has done in his photo.


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## Rustedthrough (Aug 19, 2014)

The adapters won't dramatically change your weight distribution. A loaded bike will feel more top heavy than an unloaded bike, unless the load is held low. I found it felt strange for the first few trips and became normal after 20 miles or so of stop and go city riding.

A suitcase of beer strapped to the rack deck is still more unwieldy than the same weight distributed between two side mounted bags.


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## newfangled (Sep 13, 2010)

The Gravity's dropouts are trackends, so those bontrager adapters wouldn't really serve any purpose. 

You'd only need them if you have hooded dropouts like the Diamondback, or really tight clearances like the Kona with it's sliding dropouts.


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## Rustedthrough (Aug 19, 2014)

Wouldn't the adapters raise the rack height and tire clearance? Or would they simply not work on the Gravity?


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## newfangled (Sep 13, 2010)

^ I guess you're right. But otherground's not actually using them for height - they're at the same height as the axle:









All of the extra height comes from angling the axiom feet way down.

So if a frame doesn't have hooded dropouts or giant slider bolts like the Unit, then I'd try to get it working with the axiom feet first.


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## Rustedthrough (Aug 19, 2014)

Looking back over the photos, it seems like the disc brake hardware would be in the way of the Axiom mounting plates if they were mounted straight up from the QR. The P- clamps move them forward of the caliper set- up, and the Bontrager adapters move them behind it.

Otherground. Did you try mounting the Axiom plates backwards to shorten the stay length?

I may be wrong, but, I'm learning. Thanks all for your patience.


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## vassock (Jun 29, 2009)

Rustedthrough said:


> Looking back over the photos, it seems like the disc brake hardware would be in the way of the Axiom mounting plates if they were mounted straight up from the QR. The P- clamps move them forward of the caliper set- up, and the Bontrager adapters move them behind it.
> 
> Otherground. Did you try mounting the Axiom plates backwards to shorten the stay length?
> 
> I may be wrong, but, I'm learning. Thanks all for your patience.


 Rustedthrough so what is the final decision regarding that solution you mentioned? Will it or will it not work on my bike?


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## Rustedthrough (Aug 19, 2014)

I can't see why it wouldn't work, however, finding some 3/4" or 7/8" p clamps might be a simpler installation.

Have you had any problems with the mounts you have?


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## otherground (Mar 16, 2015)

Oh hey guys, been busy with work and all. I rotated the plates for my rack 90° to give it height, if i didn't it would have been rubbing the tire.


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## vassock (Jun 29, 2009)

Rustedthrough said:


> I can't see why it wouldn't work, however, finding some 3/4" or 7/8" p clamps might be a simpler installation.
> 
> Have you had any problems with the mounts you have?


Says product is no longer available.


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## Rustedthrough (Aug 19, 2014)

Which product? What vendor?


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## vassock (Jun 29, 2009)

Rustedthrough said:


> Which product? What vendor?


Post 51 Bontrager.


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## vassock (Jun 29, 2009)

vassock said:


> Post 51 Bontrager.


So that's it? There is nothing else in stock?


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## Rustedthrough (Aug 19, 2014)

Have you tried ordering through Trek?


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## vassock (Jun 29, 2009)

Rustedthrough said:


> Have you tried ordering through Trek?


I can't find it on their website.


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## Rustedthrough (Aug 19, 2014)

Bontrager BackRack Parts - Racks - Accessories -Trek Store


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## wschruba (Apr 13, 2012)

FYI, the link comes up as a cargo net for me.

On that subject, I love a good cargo net


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## Rustedthrough (Aug 19, 2014)

Much to be said for a good cargo net. Though I prefer cams to bungees when I can get them.

Once you have clicked the link, you will have to click other things to find the adapters. Stainless, Lightweight stepped dropout kit, for use with lightweight rack (in stock $7.99).


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## vassock (Jun 29, 2009)

Rustedthrough said:


> Much to be said for a good cargo net. Though I prefer cams to bungees when I can get them.
> 
> Once you have clicked the link, you will have to click other things to find the adapters. Stainless, Lightweight stepped dropout kit, for use with lightweight rack (in stock $7.99).


So I got it and it looks like all of the holes are a few times smaller than the bolt at the dropout. Actually, I don't see what the point of these is. All they would do is adjust the rack's lower connection placement further back. I thought they would allow me to attach something to the dropout bolt that has a smaller mounting hole diameter. I think it's a bit like the "broken" axle in this video that the guy zooms up on after he removes the wheel.


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## Fergy (May 19, 2015)

Hey, I'm new to the forum. Trying to install an Axiom Journey "Uni-Fit" MK3 on a 2010 Raleigh XXIX (Single Speed 29'er).
I was REALLY struggling to find the Bontrager Back Rack Light Weight Dropout Plates Kit mentioned earlier in this thread (I heard about it from the already mentioned Amazon product review). So I wanted to say thanks to @Rustedthrough; the recent post describing how to use the poorly designed Bontrager/Trek website to order this part was a big help. (Well, at least I found the part.)
I'm still going to have to p-clamp the upper arms to the seat stays 'cause this bike has no connection points.

And here's a recent pic of my bike. (I changed the pedals and grips since this was taken.) And whenever I manage to get this rack mounted I'll come back and post again...


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## Rustedthrough (Aug 19, 2014)

Glad it looks promising Fergy. I was just restating directions from Otherground in that post. You might consider swapping out your seat post clamp and connecting the upper struts there if you are looking at supporting the rack with 4 p clamps.

Best of luck, welcome.


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## Fergy (May 19, 2015)

Wasn't too happy to pay more for shipping ($8) than for the part ($7.99) so I called the local Trek shop with the part number for this Lightweight Stepped Dropout Kit. (Trek part number is 428715). They charged me $7.99 and said they'd have it for me on Tuesday or Wednesday!


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