# Converting Trek 8000 from V to Disc Brakes



## DePo52 (Jun 1, 2015)

Hey guys, 

Brand new here. I've had a road bike for quite a while but only ride recreationally and certainly wouldn't consider myself an expert on anything. I am just about to purchase my first hard tail and I'm looking at a 2001 Trek 8000. It has a $400 asking price which I will try and talk down a little based on blue book value, but my buddy who rides a lot is adamant that I shouldn't get a bike with V brakes because when they get wet/muddy they are dangerous. Since I am really on a strict budget, this seems like a great deal for me, but I would like to convert it to disc brakes down the line. Any idea how much that would cost? And is it worth it?

Thanks in advance!


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## TampaDave (Mar 20, 2015)

Assuming the frame has mounting points for disc brakes, and I think that one does, and the right wheels, which I doubt it has, it's not difficult to upgrade. Figure ~100 for brakes and cables. 

But. You need wheels that are disc ready, ie have someplace to bolt the disc to. New wheels are ~90 plus shipping. Buying new 26er wheels isn't a great investment unless you are really wedded to 26, like if you're on a 14inch frame or something. Likewise, upgrading a 26er isn't a good investment.

It's ok to refurb a bike like this, that's not expensive. I'm redoing my 2000 trek as a 1x9 with a decent set of used XT components out back and a vintage Marzocchi fork up front. Keeping the v-brakes. I figure the cogs and chains and cables are wear items, no biggie. Those old Marzocchi forks seem to be going up in value. So I don't think I'm digging in too deep, and in any event that bike has sentimental value.

But. This is not a collectible bike, and I wouldn't say 26ers are even considered desirable these days. Don't get me wrong, I'd love to have that bike, but I would not personally go more than 250 if it's already been rehabbed, maybe 150 if it needs freshening up, and that's assuming the cranks and dr's and wheels are in really good shape. Maybe that's too cheap, but there are deals out there, don't get yourself upside down with a 26er, don't buy it for more than you can dump it for.


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## cobba (Apr 5, 2007)

DePo52 said:


> I would like to convert it to disc brakes down the line. Any idea how much that would cost?


How long is a piece of string.
Price depends on the quality of parts you want to put on it and whether they're second hand or new.

A bolt on rear brake mount will cost about $25
http://www.sellutionmtb.com/ProductDetails.asp?ProductCode=BA-GFTP

You will also need:
* a disc compatible wheelset 
* a disc brake set
* a pair of brake rotors
* depending on rotor size and mounts on the fork/frame/brake, you will probably need some front and rear PM to IS adapters



> And is it worth it?


Depends on how much you pay for the bike and the parts.

The value of a 8000 disc isn't much more then a 8000 without discs.

http://www.bicyclebluebook.com/SearchListingDetail.aspx?id=35724&make=750&model=41706
http://www.bicyclebluebook.com/SearchListingDetail.aspx?id=35723&make=750&model=53567


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## DePo52 (Jun 1, 2015)

TampaDave said:


> Assuming the frame has mounting points for disc brakes, and I think that one does, and the right wheels, which I doubt it has, it's not difficult to upgrade. Figure ~100 for brakes and cables.
> 
> But. You need wheels that are disc ready, ie have someplace to bolt the disc to. New wheels are ~90 plus shipping. Buying new 26er wheels isn't a great investment unless you are really wedded to 26, like if you're on a 14inch frame or something. Likewise, upgrading a 26er isn't a good investment.
> 
> ...


Sounds like a long winded "not really worth it" haha...Thanks a lot for the info! I'm in a situation right now where the budget will be tight for the next two years. My plan is to get me something that I can ride consistently for a couple years and then just dump it and upgrade to a brand new bike. If I'm looking at a couple hundred dollars plus some time to make it happen, I'll just keep searching for something with disc brakes that I don't have to mess with. Thank you again. Appreciate it.


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## DePo52 (Jun 1, 2015)

cobba said:


> How long is a piece of string.
> Price depends on the quality of parts you want to put on it and whether they're second hand or new.
> 
> A bolt on rear brake mount will cost about $25
> ...


All good points.


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## Shayne (Jan 14, 2004)

Discs are unnecessary.
V-brakes are not dangerous.

Buy that couple hundred dollar bike (if it fits), ride it lots, then decide if you want to buy something more modern with bells and whistles.


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## rangeriderdave (Aug 29, 2008)

I rode a lot of years with rim brakes ,canti's V,s roller cams in all kinds of weather . Don't remember one crash that I could blame on the brakes.Disc's are nicer.


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## Shakester (Jun 26, 2012)

I don't recall having any problems with rim brakes and when I was riding those, I was a lot more aggressive on the trail and i use to ride in rain and mud. Plenty of crashes and injuries but none due to the rim brakes not stopping or doing something weird.


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## 70sSanO (Nov 20, 2013)

Before you start, I think you need to find out what you need to do to get disc brakes to fit on the frame. Just because there are a couple of mounting holes doesn't mean things will just bolt on.

My son has a 2000 Trek 8500 and when I did a search on converting to disc brakes most of the information made it sound like an adapter nightmare. He is still running V-brakes.

John


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## TampaDave (Mar 20, 2015)

DePo52 said:


> Sounds like a long winded "not really worth it" haha...Thanks a lot for the info! I'm in a situation right now where the budget will be tight for the next two years. My plan is to get me something that I can ride consistently for a couple years and then just dump it and upgrade to a brand new bike. If I'm looking at a couple hundred dollars plus some time to make it happen, I'll just keep searching for something with disc brakes that I don't have to mess with. Thank you again. Appreciate it.


Or, call the guy up and gripe about the brakes, and read my post to him, and tell him you'll give him 250 for the bike. See what he says. It's a nice bike. Back in my day, we didn't have no fancy disk brakes. We stopped the bike with our bare feet, life Fred Flinstone, and we liked it. No: we loved it. Next spring, sell it for what you paid for it and get on a nice Jones titanium, gtg.


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## Adroit Rider (Oct 26, 2004)

Resurrecting this thread. I'm trying to add disc brakes to a 2001 Trek 8000. Just had it powder coated and already had the wheels and brakes in the parts bin.
I have the A2Z adapter but my efforts so far with two different IS to PM adapters leave me shopping for an IS brake. Has anyone been able to put a disc brake on with an IS PM adapter? I've seen pictures of a few bikes from this era but the rear triangle on the XS I am building is compact and a few MM of brake and adapter need to be machined off.
Link to pics, the last one is a Klein with same chain stay as the Trek 8000:





V brake to disc brake upgrade on TREK 8000


So i'm busy upgrading an old TREK series 8000 from V-Brake to Disc Brake. The fork mount is no problem, but the rear is 22mm post mount which I need to convert to ISO mount with an adaptor, like in the pictures. Does anyone have one laying around or know where I can get one




community.bikehub.co.za


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## rangeriderdave (Aug 29, 2008)

You would have an easier time just leaving the rear brake as is, while having a disc in the back is nice , it's not totally necessary . Around 80% of your braking power comes from the front. Back in the day nobody had discs and some of us lived to tell about it. I ran a disc in the front only for around 5 years.

Sent from my LM-X220 using Tapatalk


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## Adroit Rider (Oct 26, 2004)

rangeriderdave said:


> You would have an easier time just leaving the rear brake as is, while having a disc in the back is nice , it's not totally necessary . Around 80% of your braking power comes from the front. Back in the day nobody had discs and some of us lived to tell about it. I ran a disc in the front only for around 5 years.
> 
> Sent from my LM-X220 using Tapatalk


Totally. My 1996 Klein Adroit is a Mullet and I ride it with no concerns. I've got XTR V Brakes ready to go and some hand built rim brake wheels in the parts bin.

But, I also picked up a Reba RL disc only for this build and have some recently rebuilt Sram XO brakes nearly installed. I've drilled the cable stops for full length housing...

So, easy isn't what this build is about.

I'm now just debating machining the brake or getting some XTR 975 IS brakes (like in the first picture in the above link). I want to use the XOs because this is a Shimano free build so far. Other options include using a a different IS PM adapter because the Sram adapters aren't putting the brake anywhere close. I have a 40mm adapter on now with a 180mm rotor and even if I machine the caliper it's not clamping the full rotor.

If I machine the caliper mounting hole it does compromise safety but this is for a 10-12yo that is gonna maybe be 110lbs when done with this bike.

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## cobba (Apr 5, 2007)

Adroit Rider said:


> I'm now just debating machining the brake or getting some XTR 975 IS brakes (like in the first picture in the above link). I want to use the XOs because this is a Shimano free build so far. Other options include using a a different IS PM adapter because the Sram adapters aren't putting the brake anywhere close. I have a 40mm adapter on now with a 180mm rotor and even if I machine the caliper it's not clamping the full rotor.


Another option is using a flat mount caliper.....

22mm chain stay disc brake adapter
&
Homegrown Converted to 700c with new alternate Hayes 22mm Adapter | BonusTomato.com


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## Adroit Rider (Oct 26, 2004)

cobba said:


> Another option is using a flat mount caliper.....
> 
> 22mm chain stay disc brake adapter
> &
> Homegrown Converted to 700c with new alternate Hayes 22mm Adapter | BonusTomato.com


I like the flat mount custom route. It's interesting how the 22mm from long ago has been reborn with the flat mount standard. A bit different but really the same.

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## milehi (Nov 2, 1997)

i would take a Scotchbrite pad to the brake track and get the best V brake pads for your locality.


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## Adroit Rider (Oct 26, 2004)

milehi said:


> i would take a Scotchbrite pad to the brake track and get the best V brake pads for your locality.


Yes, I have a set of mechanicals so I could have matching levers but the wheel set wouldn't match. Struggling with this. I could get a close match if I can find a silver Crossmax 26" disc front as I have a silver rim brake as a potential rear.

But, the price of the front wheel and time to find it might be more than going the custom adapter route.

I was originally planning to stay with the rim brakes but I could not find a soft spring for the OEM Judy Race.

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## Harold (Dec 23, 2003)

Another one from just recently. I asked him to post a writeup in the DIY forum and I think he's going to end up posting the drawings, too, so folks can track down someone to make the part for them.









22mm chain stay disc brake adapter


I also need a 22mm brake for an Attitude I saw the right hayes rear caliper on ebay, but someone swooped it last night :( What is the consensus on the A2Z AD PMR? It should convert 22mm flat mount to IS, and you can use an adapter to attach any caliper that fits in the space. Are there any...




www.mtbr.com


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