# Bontrager Race - Rigid or Suspended Geometry?



## jpo (Jan 15, 2004)

Hi

How would I tell if the 1994 Bontrager Race frame I am looking at purchasing is made for a suspenison or rigid fork?

thanks
John


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## DeeEight (Jan 13, 2004)

hardly any difference for a 1994, the "suspension" they had in mind was a Mag-21, which with its whopping 48mm of travel was barely longer than a rigid fork.


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## Boy named SSue (Jan 7, 2004)

jpo said:


> Hi
> 
> How would I tell if the 1994 Bontrager Race frame I am looking at purchasing is made for a suspenison or rigid fork?
> 
> ...


I have the printed '94 BikePro catalogue. It lists both options for '94 Bontragers if I remember correctly.

If you are looking to run the origional Bontrager rigid fork, the difference would be a bit more than D8 might suggest. I have two large Bontragers sporting the bonty fork, one meant for the 65mm forks and a '92 built for the bonty fork. There is a huge difference between how each bike rides.

One built for the 48mm fork wouldn't be so bad. It all depends on what you are looking to do with it. A frame meant for the 48mm fork would ride well with a 65mm fork but probably not with an 80mm. Going to a shorter fork would make the handling a little too quick of handlers as they already had quick handling.

cheers


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## laffeaux (Jan 4, 2004)

jpo said:


> Hi
> 
> How would I tell if the 1994 Bontrager Race frame I am looking at purchasing is made for a suspenison or rigid fork?
> 
> ...


According to a souorce form back in the day (see below), the non-suspended version has a 73 degreee seat tube angle, and the suspended is 74 degrees. Also, the top tube on the susupended is shortened by 1/2 cm.

http://www.mtb-kataloge.de/Bikekataloge/PDF/Bontrager/Bericht_Bicycle_Guide92.pdf


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## laffeaux (Jan 4, 2004)

laffeaux said:


> According to a souorce form back in the day (see below), the non-suspended version has a 73 degreee seat tube angle, and the suspended is 74 degrees. Also, the top tube on the susupended is shortened by 1/2 cm.


Hmmm... witht hat in mind it seems that runnig a suspenion fork on a non-suspended frame would be no real big deal. The seat tube would be slackened a bit more (maybe to 72 degrees). However running rigid on a suspended model would make the already steep seat tube angle even steeper, which is probably a little less appealing.

I kind of agree with DB that in the whole scheme of things it's probably not a big deal. I've run a rigid, 63mm, 70mm, and 80mm on Bontragers at various times (most of them suspended models) and the changes in steering are very minimal. In some cases the difference in axle to crown heights varies more my fork manufacturer or model than it does by fork travel.


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## Fillet-brazed (Jan 13, 2004)

laffeaux said:


> Hmmm... witht hat in mind it seems that runnig a suspenion fork on a non-suspended frame would be no real big deal. The seat tube would be slackened a bit more (maybe to 72 degrees). However running rigid on a suspended model would make the already steep seat tube angle even steeper, which is probably a little less appealing.
> 
> I kind of agree with DB that in the whole scheme of things it's probably not a big deal. I've run a rigid, 63mm, 70mm, and 80mm on Bontragers at various times (most of them suspended models) and the changes in steering are very minimal. In some cases the difference in axle to crown heights varies more my fork manufacturer or model than it does by fork travel.


Didnt Bontrager have a specific model for running a front fork? SOmething like the Bontrager RS or something like that?? That might have been before 94 however. I know weve talked about it here and even seen a magazine article on this particular model and seen a frame, but I just cant remember the name of it.


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## Boy named SSue (Jan 7, 2004)

Fillet-brazed said:


> Didnt Bontrager have a specific model for running a front fork? SOmething like the Bontrager RS or something like that?? That might have been before 94 however. I know weve talked about it here and even seen a magazine article on this particular model and seen a frame, but I just cant remember the name of it.


I don't have it with me but I think the BikePro catalogue form '94 listed the suspended model as the RS. You are indeed correct. I think '94 was one of the years where you could get a Bontrager setup for a rigid or suspension fork. I doubt they did it much longer than that other than customs.


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## laffeaux (Jan 4, 2004)

Yeah there were two models back in the day: Bontrager OR and Bontrager ORRS

That's "Off Road" and "Off Road RockShox"


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## jpo (Jan 15, 2004)

Hi

Thanks for the info. I thought I saw somewhere in cyberspace a listing for the geometrys of the two different models. Does anyone know where this is? 

The bike now has a 96 or 97 RS Judy with the black bonty crown. I am trying to figure out if thie frame was made to have this fork or a rigid fork. i would really like the opportunity to run both. Did Bonty ever make a suspension correct rigid fork?

thanks john


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## Fillet-brazed (Jan 13, 2004)

jpo said:


> Hi
> 
> Thanks for the info. I thought I saw somewhere in cyberspace a listing for the geometrys of the two different models. Does anyone know where this is?
> 
> ...


No, there was never a susp. corrected rigid. There is a magazine article posted on this here forum on the model designed to use a susp. fork. If you search for it it should turn up...


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## cdeger (Jan 18, 2004)

Fillet-brazed said:


> No, there was never a susp. corrected rigid. ...


Fb,

what's your comment on those two different crown designs then? Just took them out of the box


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## Fillet-brazed (Jan 13, 2004)

cdeger said:


> Fb,
> 
> what's your comment on those two different crown designs then? Just took them out of the box


Hmm. I dont think Ive ever noticed a crown like yours on the left. I should admit Im not a Bontrager buff. So, I take it that crown on the left sorta "met in the middle" of the axle to crown measurement of the standard fork and the susp. fork?? Looks like its only an inch longer or so?


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## GrumpyOne (Jan 7, 2004)

Bontrager made a few suspension corrected rigid forks, but not many. They had longer legs, not a different crown. Remember that they made their own crowns for RS Mag forks, I believe that's what you have on the left. Although I pulled a drop crown like that off a RS Mag and just used it with rigid Bonti blades and it worked out well. Just not as long as an actual suspension corrected fork. (The drop crown only made the fork about 12mm longer.)

jw

BTW - Bontrager stopped making rigid forks when RockShox had all the recalls on the Mag forks due to failing crowns. KB replied to a message on rec.bicycles.tech and stated that.



cdeger said:


> Fb,
> 
> what's your comment on those two different crown designs then? Just took them out of the box


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## Fillet-brazed (Jan 13, 2004)

GrumpyOne said:


> Bontrager made a few suspension corrected rigid forks, but not many. They had longer legs, not a different crown. Remember that they made their own crowns for RS Mag forks, I believe that's what you have on the left. Although I pulled a drop crown like that off a RS Mag and just used it with rigid Bonti blades and it worked out well. Just not as long as an actual suspension corrected fork. (The drop crown only made the fork about 12mm longer.)
> 
> jw
> 
> BTW - Bontrager stopped making rigid forks when RockShox had all the recalls on the Mag forks due to failing crowns. KB replied to a message on rec.bicycles.tech and stated that.


The early Rockshox (RS-1) used the crown on the right. The later Mag (1992) forks had a crown all their own. If its true that Bontrager stopped making forks when RS had teh problems with the early crown then that would mean they stopped making them in 91. Is that true? Seems like they went for a little longer than that.

That said, a suspension corrected rigid fork wouldnt really be an item with any appeal until probably 92 at the very earliest and most likely 93...

Has anybody else heard of a suspension corrected Bontrager fork??


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## GrumpyOne (Jan 7, 2004)

Straight from the horses mouth: rec.bicycles.tec KB Fork Info

jw

PS The photo is of my current Bontrager rigid forks.



Fillet-brazed said:


> The early Rockshox (RS-1) used the crown on the right. The later Mag (1992) forks had a crown all their own. If its true that Bontrager stopped making forks when RS had teh problems with the early crown then that would mean they stopped making them in 91. Is that true? Seems like they went for a little longer than that.
> 
> That said, a suspension corrected rigid fork wouldnt really be an item with any appeal until probably 92 at the very earliest and most likely 93...
> 
> Has anybody else heard of a suspension corrected Bontrager fork??


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## jpo (Jan 15, 2004)

So how would I tell if this 1994 frame is made with the rigid or suspension geometry?

John


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## GrumpyOne (Jan 7, 2004)

Sorry for taking you way off topic. I haven't figured out a good way to tell other then to build the frame up and measure the angles. On a bare frame there isn't any way to tell just by measurements alone. After you build the frame up, you can check the frame angles with a angle meter (see photo).

jw



jpo said:


> So how would I tell if this 1994 frame is made with the rigid or suspension geometry?
> 
> John


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## jpo (Jan 15, 2004)

ok. I was kind of afraid of that. The frame is not built up and it does not have a headset for the fork. it will be difficult to get any accurate measurements.

Thanks
John


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## Rumpfy (Dec 21, 2003)

cdeger said:


> Fb,
> 
> what's your comment on those two different crown designs then? Just took them out of the box


I picked up a Mag20 that had the steer/crown pictured on the left...

I would think it should still fit on an RS-1 fork...but not from a geometry spec standpoint.


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## Rumpfy (Dec 21, 2003)

GrumpyOne said:


> jw
> 
> PS The photo is of my current Bontrager rigid forks.


Great pic JW...pretty.

I can try and find you a more period correct tire for your Bonty though if you'd like.


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## laffeaux (Jan 4, 2004)

GrumpyOne said:


> Straight from the horses mouth: rec.bicycles.tec KB Fork Info


Cool pic!!

I read KB's post differently. He says that they stopped making the crown that was interchangable with the RS products when RS started having problems. He doesn't say that they stapped making all rigid forks.

Based on the geo listing a suspended and non-suspended frames in the '94 catalog, I'd guess that the rigid forks had to be made up until at least that time.


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## Fillet-brazed (Jan 13, 2004)

GrumpyOne said:


> Straight from the horses mouth: rec.bicycles.tec KB Fork Info
> 
> jw
> 
> PS The photo is of my current Bontrager rigid forks.


That is kinda hard to follow, I assume KB is the black writing. So Keith said they made a few that were the same length as a Mag 21, so that would be 1992 and newer. However the RS-1 did not have a crown like your long legged fork has, they were like the other two you have in the shot that arent mounted. Thats cool you have one of those suspension length forks. He also mentioned there were some made that had 7/8" offset. Kinda interesting.


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## Fillet-brazed (Jan 13, 2004)

Rumpfy said:


> I picked up a Mag20 that had the steer/crown pictured on the left...
> 
> I would think it should still fit on an RS-1 fork...but not from a geometry spec standpoint.


Really? With the bolts on the front or on the side?


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## Fillet-brazed (Jan 13, 2004)

jpo said:


> ok. I was kind of afraid of that. The frame is not built up and it does not have a headset for the fork. it will be difficult to get any accurate measurements.
> 
> Thanks
> John


I think someone said the supsension corrected frame has a half inch shorter top tube.

Edit: ya, the suspension corrected has a steeper seat tube making the top tube a bit shorter. *IF* these have perfectly level top tubes, which I think the old ones did, you can position your frame in a stand and level out the TT with a level or an angle meter, then check the seat tube angle once you have that. This should tell you whether is 73 (non susp. corrected) or 74 (susp. corrected).


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## laffeaux (Jan 4, 2004)

Fillet-brazed said:


> I think someone said the supsension corrected frame has a half inch shorter top tube.
> 
> Edit: ya, the suspension corrected has a steeper seat tube making the top tube a bit shorter. *IF* these have perfectly level top tubes, which I think the old ones did, you can position your frame in a stand and level out the TT with a level or an angle meter, then check the seat tube angle once you have that. This should tell you whether is 73 (non susp. corrected) or 74 (susp. corrected).


The older ones have a top tube with less slope, but they still have some slope. My newer one loses about 2.5" along the top tube, and the old-style one loses just under 1.5".


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## Rumpfy (Dec 21, 2003)

Fillet-brazed said:


> Really? With the bolts on the front or on the side?


Front. Just like the one in the picture above...I'll take a pic of mine when I get unlazy.


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## cdeger (Jan 18, 2004)

*Not my mother's tongue but ...*



laffeaux said:


> Cool pic!!
> 
> I read KB's post differently. He says that they stopped making the crown that was interchangable with the RS products when RS started having problems. He doesn't say that they stapped making all rigid forks.
> 
> Based on the geo listing a suspended and non-suspended frames in the '94 catalog, I'd guess that the rigid forks had to be made up until at least that time.


... I'm sure I understand what Keith meant. Listen, buddies:

"There were a handful of rigid straight blades made to the same (nearly)
length as a Mag 21. These allowed one to interchange the blades for
the suspension legs *i the Rockshox crown*. Sounds like that's what you
have.

We decided to stop after a few were sold because of the *problems
RockShox was having with crowns* (recalls). Didn't want to be a part
of that action, and the rigid fork seemed like it would only be
worse than the suspension unit. "

Those longer Bontrager legs fitted into RockShox' Mag21 crowns. => RockShox realized that they had reliability problems => Keith didn't want to be involved as his rigid fork legs would increase the load on those fork crowns.

Got it?


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## Eli-Ti (Sep 10, 2004)

*bonty crowns...*

If I remember correctly...
Those bonty crowns are cool when paired with a bonty frame, especially the judy ones. If the frame you have comes with a black Judy crown like the ones in that picture then it should be a mated set which is even better. The reason Bontrager made those crowns is to give the forks a different rake than Rock Shox offered. They are supposed to have a better ride quality to them. If the head-tube angle is funky, this is because it should be mated ideally to one of these crowns. If it is mated to the Judy crown I'd say odds are that this is a set and you lucked out.... good bike.


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## Joe Steel (Dec 30, 2003)

*Suspension with Rigid*

I have a ~'95 (?) (that I believe has suspension corrected geometry) built up as a singlespeed with a Bontrager rigid fork. I searched around for a 1" suspension fork but decided to try this rather then suffer through the headaches of trying to keep an old 1" suspension fork "alive".

I rode 30 miles on this last weekend over a mix of singletrack and fire roads and had an absolute blast.

One of these pics may give an impression of the angles (compared to the photo of rigid geometry version in the brochure).


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## Rumpfy (Dec 21, 2003)

Eli-Ti said:


> If I remember correctly...
> Those bonty crowns are cool when paired with a bonty frame, especially the judy ones. If the frame you have comes with a black Judy crown like the ones in that picture then it should be a mated set which is even better. The reason Bontrager made those crowns is to give the forks a different rake than Rock Shox offered. They are supposed to have a better ride quality to them. If the head-tube angle is funky, this is because it should be mated ideally to one of these crowns. If it is mated to the Judy crown I'd say odds are that this is a set and you lucked out.... good bike.


I've got a Judy with the zero offset Bontrager crown too...I wouldn't go so far as to say it gives you better ride quality... It makes things 'quick' thats for sure! Sorta twitchey actually. The faster you're going, the better it felt though.

(Don't let the pic fool you...it's a Judy that's been resprayed flat black with RS-1 decals....but check the steer/crown)


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## Fillet-brazed (Jan 13, 2004)

Rumpfy said:


> I've got a Judy with the zero offset Bontrager crown too...I wouldn't go so far as to say it gives you better ride quality... It makes things 'quick' thats for sure! Sorta twitchey actually. The faster you're going, the better it felt though.
> 
> (Don't let the pic fool you...it's a Judy that's been resprayed flat black with RS-1 decals....but check the steer/crown)


Zero offset! Boy, that'd be a ride! I think theyre 1.25" as opposed to 1.6". Should be more stable with the shorter offset, it increases the trail.


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## Rumpfy (Dec 21, 2003)

Fillet-brazed said:


> Zero offset! Boy, that'd be a ride! I think theyre 1.25" as opposed to 1.6". Should be more stable with the shorter offset, it increases the trail.


Sorry....'reduced' offset.

Picky, picky. 

Have you unbroken the record set on the Sling yet?


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## Fillet-brazed (Jan 13, 2004)

Rumpfy said:


> Front. Just like the one in the picture above...I'll take a pic of mine when I get unlazy.


I wont hold my breath. 

Interesting, Ive never seen this crown on a Rock Shox.


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## Boy named SSue (Jan 7, 2004)

Fillet-brazed said:


> The early Rockshox (RS-1) used the crown on the right. The later Mag (1992) forks had a crown all their own. If its true that Bontrager stopped making forks when RS had teh problems with the early crown then that would mean they stopped making them in 91. Is that true? Seems like they went for a little longer than that.
> 
> That said, a suspension corrected rigid fork wouldnt really be an item with any appeal until probably 92 at the very earliest and most likely 93...
> 
> Has anybody else heard of a suspension corrected Bontrager fork??


I haven't ever heard of a bonty suspension corrected fork either.

As for when they ended production on the rigid fork, the '94 BikePro catalog still lists them as available as they list two frame choices, the RS and standard. They probably made them untill they switched full to suspension corrected frames ( '95?) and if they ever did make the suspension corrected fork, it probably would have been part of this transition.

I wish I had the catalog with me but I think it is stashed in Mom's garage.


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## GrumpyOne (Jan 7, 2004)

Boy named SSue said:


> I haven't ever heard of a bonty suspension corrected fork either.


Here's a photo of one. But remember we're talking about RockShox Mag corrected fork (ie very short travel).

jw


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## Fillet-brazed (Jan 13, 2004)

GrumpyOne said:


> Here's a photo of one. But remember we're talking about RockShox Mag corrected fork (ie very short travel).
> 
> jw


Is that supposed to be the same length as a Rock Shox fork? Thats gotta be shorter than an RS1 or Mag fork. They had 2" of travel and probably 2.25" atleast of clearance between crown and tire... Ive got an RS-1 I could measure the axle to crown distance on if you want to measure yours for comparison's sake...

Edit: heres a side shot of an RS-1. Quite a bit taller than the susp. corrected Bontrager. https://gallery.mtbr.com/data/mtbr/560/233423pros9.jpg


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## GrumpyOne (Jan 7, 2004)

I agree it looks short. But my Sutherland's RockShox Handbook lists the following:
- 46mm travel Mag 20 & 30 - 402mm (Axel to Crown)
- 46mm travel Mag 10 & 21 - 406mm
- 60mm travel Mag 21 - 420mm​And those were measured by Sutherland's, not the RS published numbers. The fork pictured (which is not mine) measured out at 403mm and mine(silver fork) measures at 405mm. And for comparison, my standard Bontrager forks all measure 385mm axel to crown.

jw



Fillet-brazed said:


> Is that supposed to be the same length as a Rock Shox fork? Thats gotta be shorter than an RS1 or Mag fork. They had 2" of travel and probably 2.25" atleast of clearance between crown and tire... Ive got an RS-1 I could measure the axle to crown distance on if you want to measure yours for comparison's sake...
> 
> Edit: heres a side shot of an RS-1. Quite a bit taller than the susp. corrected Bontrager. https://gallery.mtbr.com/data/mtbr/560/233423pros9.jpg


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## laffeaux (Jan 4, 2004)

GrumpyOne said:


> And for comparison, my standard Bontrager forks all measure 385mm axel to crown.


Yep, mine measures right at 385mm. You certainly have more tire clearance that I do - I have less than 3/4" between the crown and tread (it's a 2.4" WTB tire though).


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## Fillet-brazed (Jan 13, 2004)

GrumpyOne said:


> I agree it looks short. But my Sutherland's RockShox Handbook lists the following:
> - 46mm travel Mag 20 & 30 - 402mm (Axel to Crown)
> - 46mm travel Mag 10 & 21 - 406mm
> - 60mm travel Mag 21 - 420mm​And those were measured by Sutherland's, not the RS published numbers. The fork pictured (which is not mine) measured out at 403mm and mine(silver fork) measures at 405mm. And for comparison, my standard Bontrager forks all measure 385mm axel to crown.
> ...


Ok, just measured a RS1 and a Mag21.

RS1=420mm axle to crown
Mag21+ 413mm axle to crown

Both have the 49mm travel or whatever RS claimed it as.

Maybe Sutherlands didnt pump up their forks all they way? Kinda weird.


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## scooderdude (Sep 27, 2004)

Joe Steel said:


> I have a ~'95 (?) (that I believe has suspension corrected geometry) built up as a singlespeed with a Bontrager rigid fork. I searched around for a 1" suspension fork but decided to try this rather then suffer through the headaches of trying to keep an old 1" suspension fork "alive".
> 
> I rode 30 miles on this last weekend over a mix of singletrack and fire roads and had an absolute blast.
> 
> One of these pics may give an impression of the angles (compared to the photo of rigid geometry version in the brochure).


Damn it, Joe - I still want your frame!!


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## flyingsuperpetis (Jan 16, 2004)

cdeger said:


> Fb,
> 
> what's your comment on those two different crown designs then? Just took them out of the box


 Cdeger, did I sell you those? Ah well, I've got a Bonty fork going up for sale thurs, but it's not the suspension-corrected model, so not much help. I'll get an mtbr ad & post it when it & everythign else goes up...


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## Rumpfy (Dec 21, 2003)

Fillet-brazed said:


> I wont hold my breath.
> 
> Interesting, Ive never seen this crown on a Rock Shox.


Alright, alright...I got unlazy.

The fork on the right is a complete RS-1 with the correct crown.
The one on the right is with a steer/crown I pulled from a Mag20 with the little Bontrager dot decal on it. Bolts are front and back, not on the side.


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## Fillet-brazed (Jan 13, 2004)

Ya, the one on the right is normal, the one on the left Ive never seen before on a Rockshox. I wouldnt think RS would sell a fork with a Bontrager sticker on the crown. Are you the original owner of the Mag that had the Bontrager crown? What Im getting at is Im guessing somebody put it on there and removed the other crown. But according to all the info posted above supposedly Bonty did do some Mag crowns... Who knows.


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## Rumpfy (Dec 21, 2003)

Fillet-brazed said:


> Ya, the one on the right is normal, the one on the left Ive never seen before on a Rockshox. I wouldnt think RS would sell a fork with a Bontrager sticker on the crown. Are you the original owner of the Mag that had the Bontrager crown? What Im getting at is Im guessing somebody put it on there and removed the other crown. But according to all the info posted above supposedly Bonty did do some Mag crowns... Who knows.


Hmmm...not sure. It was on one of the Epic's I picked up. The Mag20 was pretty beat down, but this was the crown that was on it. I didn't know there was a difference in steer/crowns at the time and sold off the rest of the fork as parts.
I guess there's a chance it was added to the Mag at a later date...could it be from a Bontrager fork? Or perhaps the decal added afterwards...


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## Rumpfy (Dec 21, 2003)

Rumpfy said:


> Hmmm...not sure. It was on one of the Epic's I picked up. The Mag20 was pretty beat down, but this was the crown that was on it. I didn't know there was a difference in steer/crowns at the time and sold off the rest of the fork as parts.
> I guess there's a chance it was added to the Mag at a later date...could it be from a Bontrager fork? Or perhaps the decal added afterwards...


Perhaps very early Mag20's?


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