DeanSams

I completely agree. Its versatility helps clear the clutter of bike we own.

AdventureManCO 

I didn't want this thread to die an untimely death, so onward it goes

One of my main commuters is a '96ish Trek 990 with 700c wheels. I've never noticed any BB height issues. Is that a big deal? To me it hasn't been. I wanted a no-frills, lightweight, Made-in-USA frameset. I know that it is no custom, but compared to custom tigged frames, the value here made sense. These bikes slip under the radar because they are fairly pedestrian, they made a lot of them, and doesn't have the cult status of more memorable brands like Moots or Fat Chance. I found this one disguised on craigslist as a mundane 'mountain bike', hidden under mediocre parts.

Biggest issue so far is the rear brake. I like the idea of fabricating a bracket to move v-brakes up a bit, but I'm not sure that the Trek's rear brake posts can unscrew, so I'll have to overcome that challenge eventually. Right now I drilled out the rear seatstay bridge to accept a road caliper and that is working, but barely - w/ cross levers and old pads, its a bad combo.

My goal was to build up an all-metal (no carbon) commuter that was light yet durable. The Trek 990 frame is great - True Temper OX Comp III tubing. It is very light. The fork is a steel 700c cross fork from the bay, but has a little more flex than I like. My ideal build would be get a custom made fork (waltworks, etc) and pick the front end up just a little bit. Who knows what that would do to the BB height, but I've never noticed that anyway. The headtube on these older mtbs is so short! Set it up as a 1x8 and it is a great, smooth rider. Plenty of tweaks to make and things to fix...but that is why I love riding it! Something new to change, adjust, etc. Never boring. It is still in what I'd call a 'shakedown' phase - not pretty, plenty of mismatched stuff, dirty, scratched, etc. Once the build gets sorted out more, that will all change. More changes to come will be different levers, a lighter headset, beartrap style pedals (from my bmx days!), ti BB, 50mm riser bars, foam grips, and then a strip and refinish.

If you can find an old 90s mtb with a decent tubeset and a 1 1/8 compatible headtube, these make for fun bike projects. Really enjoying it.








I think these 700c conversions shouldn't be written off. I commuted on my 3x9 sti-equipped Scott speedster today (24mi), and think I enjoyed riding my little homebrew even more. Then again, that could just be the romance speaking, but hey, isn't that what this is all about, anyway? Carry on

Tulok

I could have sworn there was a much older thread with more of these... some were really good! Like some of the ones in here, they looked natural and really decent.

clubman 

+1 Conti Goliaths and Town & Countries were my 90 psi tires. Fast.

Lascauxcaveman 

Depends on the frame geometry (ALL over the map on MTBs 1984 - 2000), the size of the tires and the rider, of course. On my Nishiki, upthread, it was very noticeable. The bike felt OK while riding, even very solid on those 35mm tires, but mounting and dismounting was a alien experience.

For me, that was the fun and easy part. I saw a picture of an ExtraCycle brake conversion plate online and said "Hello, sabresaw" and made my own from an aluminum plate I had on hand. Couple of nuts and bolts and spacers and I was in business. A bit clunky, but functional:



It's almost a shame that's the only part that has to go when I convert it back to 26" on the rear

CliffordK

I've posted my Litespeed conversion from time to time, when big/small wheels come up.

However, you're not thinking of the Drop Bar Conversion Thread, are you?

Tulok

Your Litespeed is definitely one I remember! It looks great!

I’ve been doing some calculating and measuring and I really thought some old MTB’s share similar frame geometry to TT bikes if modified slightly with bolt on parts.

Then i I found this:
https://www.cyclingweekly.com/news/a...ial-bike-29431

and Andy Wilkinson uses essentially a cyclocross frame with an MTB rear triangle, to win time trials, and he has rack mounts, clearance for 2.1” tires, etc etc.

Your Litespeed doesn’t look that far off of Andy’s, and if you were training for a 24hr+ effort you wouldn’t want to be switching bikes EVER for years in order to build extreme specificity.

I’m training for my eventual goal of racing the 508, so I am searching for one bike that I can always ride as well. But I am not going to buy anything wildly custom, I don’t believe it’s necessary.

Tulok

Double posting. It is the drop bar conversion thread. I just had to start from page one, which coincides almost exactly with when I saw them. 2012! Thanks!

Heres a cool one from @RaleighSport

CliffordK

I have to say... I think it is the QUADS that are winning the races!!!

Interesting bike choice. That is either a "29er", or a 700c Cross bike. So, a little different conversion.

26" to 700c is quite a bit tighter with vertical space around the tires.

Going with a MTB does force a moderately wider Q-Factor on the crankset. I think I do prefer a slightly more narrow Q-Factor from road bikes, although that may depend on a person's body build. But, going with the MTB base does give a fairly long front triangle and low bar position which would be good for TT.

I almost picked a more modern 853 MTB frame off of E-Bay, but it was a little bit longer than I needed.

When changing rim sizes, if one wanted a versatile bike for quick conversions back and forth, then disc brakes would be nice.

FlMTNdude

So my take on conversion. Having rode an 89 Panasonic Mountain Cat for over. 7000 miles on 700c x 28 tires now, I like it. The geometry is almost identical to their road bikes that I find myself easily keeping up with roadies with similar capabilities, as well as making for a great commuter with a rack and panniers.
That said, if I were to do it over again, I would do 650b (27.5). I would be able to fit a x40 tire on there for gravel and/or mud guards easily. As is, if I still had the original front fork the clearance on the front would be too tight, and the rear could maybe squeeze 30, but I doubt it. Everything as far as anyone but knowledgeable cyclists is by appearance a road bike. For the foreseeable future all that won’t change. If I find a super cheap project road frame (Panasonic DX3000 or better or one of the better Fuji like a Del Rey) then will build a new road bike and turn this into a pure gravel grinder with commuting duties.

RaleighSport

Oh I remember that setup! God it looks clean too.. may have to go back to that but with drop bars..

av1

There should be a cheaper alternatives to Paul motolite v brakes for swapping wheel sizes between 26 to 28 and even to 27,5 if available for v brakes. It could be cheaper to make a decent v brake than a decent disc brake.

sunvalleylaw

Still riding my bike that was the original motivation for my starting the thread. Last couple/few years, with a Jones Loop bar that made it even better and more versatile, IMO. I have a new Kona Libre gravel bike, so I don’t use this one much for that any more. the new carbon bike is faster, lighter, and fun. But this bike still is a go to get a rounder, grocery getter, pub hopper, cruiser, towny, just fun bike. And I can hit a little dirt or gravel if I want to along the way. Keep thinking I will replace the old Clement USH X’Plor tires, but they are still in pretty good shape and are working fine, so no need.

MrAwesome

​​​That's exactly why I came to this thread. I have a '96-ish Trek 990 frame collecting dust and one been toying with this idea for years. I didn't decide if it's worth building up as a mountain bike since I have a newer mountain bike and am about to pull the trigger on a full suspension soon. I have a FG/SS already. What to do with my steel Trek frame? I wasn't sure about 700c wheels until 29ers started pooping up. I think maybe I'll try it. I was actually thinking of using disc brakes instead of trying to adapt the Vs to for the bigger wheels. They're are adapters you can buy to retrofit discs to the frame or you can weld a bracket. And you just get a disc-ready fork. I know, it's easy to talk about it...

Do you have any photos of the Trek with 700s?

​​​​​

AdventureManCO 

Shoot, I wish I did! I had some photos up on another site, but they look broken right now and I can't find the original shots. I'll look for them. Right now the bike is in pieces (to get a frame weight...I think it is around 2250 grams for the 16") otherwise I'd just go right out in the garage and snap a pic.

The bike looked great. it was very lightweight, a great handler, nible and smooth - it felt like a good high end bicycle. It made for a great commuter, and was a fun project bike, sooo...basically the perfect bicycle lol. One thing I tend to notice about a lot of mtb to 700c conversions it that the bikes naturally seem to have a super aggressive stance - seat way up high, and bars way out forward and low. I can't really did that riding style, so mine was set up with a short stem and riser bars, putting the bars about level with the seat. I want the bars up even further, so I'm going to go with a higher rise bar or get a fork that has a higher axle to crown length.

With 700c tires on there, the wheels are honestly probably around the same-ish diameter that they would be with 26" rims and larger knobby tires, which is probably why I don't notice any bottom bracket height issues.

I like the idea of the disc brakes. I decided to go w/ standard v brakes to keep things simply and super lightweight. And it is/was a VERY lightweight ride! And it could go even lighter. I had a Cane Creek headset on there that was massive and was steel...weighed a ton. My goal is to spend a little more time on this bike and build it up using all USA parts. I know that is difficult, but hey, I need a good challenge.

Things like a Thomson seatpost and stem, King headset, phil wood bb, will make it easier. Cranks, handlebars might make that challenge a bit more interesting. But, we'll try!

MrAwesome

That sounds awesome! Yes, that's why I have kept the frame all these years. I knew it would make a really good all-around bike. I am hoping it will be similar to when I was a kid with a BMX bike that I could just have fun riding around aimlessly or even for medium distance runs to the store or whatever. I have just been going back and forth on exactly how I want to do it. I want it perfect; I don't want to throw just anything on it just to make it work, so it's been taking a long time to do the research on what I need to make it work the way I want and also not look like it was cobbled together from the junkyard. So I realize it will also cost money; another reason I didn't just jump into it immediately.

I actually measured the wheels and tires a long time ago and realized it would work. I have read many things about it messing up the geometry and I couldn't figure out why. I guess I forgot about the outside diameter being the same and I just checked it yesterday and the wheels I have that are 700c are pretty much identical to large 26" MTB tires I have on another bike, so of course it will work fine without any issues with the geometry unless I try putting 29er tires on it (which wouldn't fit anyway). It's really the brakes that are an issue, as far as I can see. And since I am thinking SS, getting the right wheels with the right hub width could be challenging, as well, but if I have to, I'll use spacers on a standard MTB wheel or build it myself.

Keep me posted on your progress. I'm interested to see how it turns out.

AdventureManCO 

Thanks for your interest! It has definitely renewed mine in picking this bike back up as a project. I'll probably build it back up again here soon just for fun and to keep the project going. These old Treks are wonderful bikes - they made a lot of them, so they are not really considered that rare or special. But the fact that you can get a decently lightweight cro-moly frame, made in usa, for $50-$150, it's pretty amazing.

The only thing that has been a bit of a challenge is the head tube - they sure made them short...which contributes to the aggressive lower front end stance. That is where a fork with a higher axle-to-crown height can come it, but they can be hard to find. This bike didn't come with it's original front end. It has some terrible old Rock Shox threaded fork that was a brick. It was a real diamond in the rough - a beautiful frame (Trek's highest end welded cro-moly mtb frame). I found a random 700c steel 1 1/8 threadless cyclocross fork to throw on there. It would be sweet to get something like a vicious cycles or a waltworks custom fork for it, but that might blow the budget a bit!

I picked up another Trek bike a year or so later - an olive green Trek 930 from 1998. Still made in USA. It was ever so slightly heavier than the '96, but would still make a fantastic commuter or lean and mean singletrack hardtail. These bike were jewels with lower quality/outdated (by today's standard) parts hung on them, but would really shine if brought up to more modern standards.

I did a raw/gun-blued frame on an older Centurion build that I did, and with a special coating is still free of rust. I think I might do the same with this Trek 990. It would look killer - gun blued frame with silver parts.

MrAwesome

Yes one of the many reasons I haven't finished is because I would like to repaint and I might be too impatient to take it all apart after building it up finally, so its better for me to leave it in pieces until I have everything I need to finish it all at once. blued sounds really cool, I have also considered a raw-ish finish. Mine is a dark gray color anyway which is very similar to what raw steel would be, so I may stick with a similar color when I finally finish it.

I agree, these frames are amazing which of course is why I bought the bike even though it was spec'd with old, beat up and out of date parts and why I stripped it down immediately. It is also why I have been torn on what to do with it. I kinda wouldn't mind building it up with modern mountain bike components and see how it does on the trails, but on the other hand, I have a slightly newer and lighter and more modern mountain bike and am probably going to pull the trigger on a FS trail bike soon, so it would probably not get ridden as much as an MTB. Also, I would hate to crash on it in the trails and ruin it. If I use it as a fun get-around-bike, it will likely last forever.

AdventureManCO 

Nothing new to report yet, but I've been thinking about it a lot. I'd really like to get a new lightweight aluminum headset before I build the thing again just so I don't have to strip it all the way down again, but I might just do it just because. I'll be visiting this thread again soon.

scarlson 

I just noticed this thread! I did a 700c conversion years ago. It was weird, but surprisingly worked fine! I put together a steel-frame, rigid-fork Specialized Hardrock with 700c wheels. Used a Sturmey Archer drum on front and rollerbrake on back. It was my commuter test mule. Handling was fine, from low speed heavily-laden Costco runs all the way up to 40mph on downhills, and clearances were sufficient for Nokian 700x37 W240 studded tires with VO Zeppelin fenders.

I hated the studs and the drum brake, but it was a cheap way of figuring that out. Built it back into an MTB and sold it to a friend, who is still using it. I wish I had a picture of it to post in this thread!

Korina

MrAwesome , curious why you don't just throw on some Rat Trap Pass tires and north road bars and ride that sucker? It'd be a perfect commuter/grocery getter/fun road bike. I honestly don't see the advantage of 700c wheels, especially these days, when we know that skinnier isn't faster, just harsher.

MrAwesome

Mainly because I don't even have wheels for it anymore, but I have been considering all options. I have some dirt tires in 26" with a smooth center and knobby edges, so those might be perfect for this build when filled up to higher pressure range. I would also like to get a rigid fork without either spending as much as a suspension fork or getting one that weighs more than a suspension fork. Those are the two items I don't have laying around, which are both crucial to any bike build and also two of the most expensive components to a bike build. The fork that came with the frame is in bad shape. I could buy some replacement springs/elastomers for the fork and use it but for this type of build, I would prefer a rigid fork. So, I'm looking at a good chunk of money, which I don't mind spending, but I want to weigh all options before I take the plunge and there are so many options and variables, it's a little overwhelming.

Korina

Ah! I didn't realize it had a suspension fork. Bummer. Have you checked out Bicycle Wheel Warehouse? They make nice wheels for decent prices.

MrAwesome

I think I have looked at every wheel website there is. I think the problem may be that I am a cheapskate, which could really hinder my build. I wish I was just missing a seat post and a saddle or something (after typing that, I realized, that is also the case). Those can be gotten fairly cheap without sacrificing looks or usability. But no, I had one up everyone. the only thing worse than missing a wheelset, is missing the frame, which sometimes I wish was the case. I have been struggling to figure out what to do with this frame without going too far overboard with cost for a very long time. I could easily spend so much money on this build that it wouldn't make any sense, but at the same time, I want something that is nice to ride and looks cool too. I don't want this great, American-made classic steel frame to look like it came from the junkyard.

Korina

I understand; things just escalate so quickly. CL donor bike? C&V for sale thread? And do you have pics of the beast in question? I'm curious.