Classic & Vintage - New fork for Peugeot UO8

Hello. Here is my bike: Peugeot UO8 (http://velospace.org/node/21084)

I am looking to upgrade it further and want to get a new fork. I want to get a straight threaded fork and I believe that the UO8 needs a 1". Anyone know where to look or anything good that would work/fit?

Thanks

May I ask what's wrong with the one currently on there? It looks nice!

Nothing is wrong with the current one but I am interesting in upgrading it further. I like the look of the straight forks and was wondering what kind of option I have with my particular frame.

One clue is the stem you have in there. What kind is it? Many French bikes had a skinnier steer tube, but not all. The French steer tube needed a stem with a slightly skinnier stem. The headset would have to be a French-dimensioned one as well.

Well, if indeed the headtube is narrower, then this is going to be a sloppy if not fruitless endeavor - finding a straight-bladed fork with a French steertube sounds like a snipe hunt to me.

If that's the case, better off finding another frame - ISO or JIS - to build this thing on top of (not to mention that the hipster aesthetics you're after look better on a narrower wheelbase which you'd get on a racier and newer frame). IMO

One clue is the stem you have in there. What kind is it? Many French bikes had a skinnier steer tube, but not all. The French steer tube needed a stem with a slightly skinnier stem. The headset would have to be a French-dimensioned one as well.
Not if he's replacing the fork. Although IMHO, a straight-blade fork would be Just Plain Wrong on a UO-8.

The UO-8 was fairly low-end, but it has a very nice ride. A replacement fork may not be any improvement -- in fact, it may make the ride quality worse if it is significantly different from the OEM fork.

That fork looks lovely. Leave it as it is, I say.

French head tubes are not narrower. The steer tube is narrower and has metric threads, so you'll need to replace your headset. You can get away with using the stem you have, even though the diameter is 0.2 mm too small. It would be better to replace it with a 22.2 stem, though.

I think it's a bad idea and will ruin the looks and handling, but it's your bike. French bikes are known for the graceful curve of their forks and that's a prime example. A carbon fiber fork will lighten the bike, but I wouldn't call it an upgrade.

Changing to a more "modern" straight fork will change the ride and handling probably even more than it will change the appearance. Even though I am in need of a fork for my own tall UO8, I'd recommend if you do find a replacement to hold on to the old fork until you are sure you are happy with the upgrade. Then, and only then, will I attempt to tempt the old fork from you.

Hijack apologies, but hold the phone! The headtube is the same size as non-French frames, so I could replace my Poog's french fork and headset w/ any old fork and modern ISO headset?? Ohhh baby. Time to make some plans!

That is interesting news. I was curious whether the fork was slightly smaller due to the the stem having to be 22mm.

I am of course not looking for a carbon fork. I agree it would ruin the look. I was more interested in one like this: Here (http://www.bikecult.com/works/parts/FKgenSB.html)

Depending on whether or not a new fork works and if I like it, I might not hold on to the original fork for long. Who knows

Do you ride it brakeless with Power Grips?

Hi Xavier853, Love the look of your bike!

It's your bike, so do what you want with it, but two things to consider before fitting straight bladed forks - and these could be "deal breakers". Firstly, will you have clearance for the front wheel under the down-tube? You could measure this by placing a steel ruler the length of your proposed forks at the correct angle against the top of your current forks. Tape it in place, then remove the wheel and place the spindle behind the ruler at the correct height. If the tyre's not touching the bottom of the down-tube you're OK.

With the wheel in this position, swing the crank forward so it's pointing straight ahead. How much does the pedal overlap the wheel? Will you be able to steer? If you're running fixed-wheel, this could be crucial.

If these are both OK, get building up the strength in your wrists! I speak from experience when I say that the vibration from straight forks can go straight into the handlebars on anything but gloss-smooth tarmac and oh boy! is it painful!

Not trying to be a party-pooper, but if you don't check these things out it could be an expensive and painful mistake. I'd check before placing any orders. Good luck!

That for has 43mm of rake, so you should be okay.

Do you ride it brakeless with Power Grips?

Yes those are Power grips, and yes there are no brakes.


Firstly, will you have clearance for the front wheel under the down-tube? You could measure this by placing a steel ruler the length of your proposed forks at the correct angle against the top of your current forks. Tape it in place, then remove the wheel and place the spindle behind the ruler at the correct height. If the tyre's not touching the bottom of the down-tube you're OK.

With the wheel in this position, swing the crank forward so it's pointing straight ahead. How much does the pedal overlap the wheel? Will you be able to steer? If you're running fixed-wheel, this could be crucial.

Very good points. I have thought of the front wheel possibly interfering with down-tube. I am almost positive that it would fit, but I will double check.

Thanks for bringing up the crank arms in the horizontal position. It is indeed fixed, so that could be a problem if there is not enough clearance.

Also I am aware of the vibration that a straight fork transfers to the handlebars compared to the curved style.

The UO8 doesnt have an overly steep headtube so I wouldnt worry what the decrease in fork rake/trail is going to do to the handling.......if the axle to crown height is similar in comparioson the original fork

My primary concern/observation would be the front ride height. A modern 700c/27" may drop the head tube as much as 1" or more which in turn increases the headtube angle. An increased headtube angle in conjuction with a low rake fork could be dangerous/twitchy.

That's a distinct possibility. Peugeot forks are extra long and the modern replacement that I've tried have been much shorter. I've been trying to find a fork that will allow me to use 38c tires with fenders. I may have to use a Peugeot fork and a French headset on a Raleigh.

I bought my similar-vintage UO-8 as a bare frame when I worked at a dealership. I equipped it with an aftermarket fork which has noticeably less rake than the OEM unit, giving me at least 5mm of toe-to-tire overlap with 165mm cranks and American size 9 shoes. The overlap has never caused a safety problem, although I have toed the front tire occasionally when turning sharply at pedestrian speed or lower, as when maneuvering in the parking lot at work. The handling is crisper than on the stock UO-8 I owned previously, and the ride is extremely smooth and stable. I find stock UO-8s to be a bit too slow in the steering for my preferences, although they are remarkably good for a bottom-of-the-line framset. In my case, I think the aluminum rims, aluminum cranks, and Japanese derailleurs (with those great SunTour barcons and a really slick 12-speed half-step shift pattern) bring out the full potential of the French frame.

So you are saying the traditional french fork is typically longer than a new straight fork I might buy?

I'm saying that your Peugeot fork is longer than most any new fork you can buy. Just look at the distance between the tire and the fork crown. They don't make them like that any more. Your fork was made to accomodate 27X1 1/4" tires and still have room for fenders.

Ok thats for all the tips and information.

I am going to do a little research on this, and maybe head over to the LBS to see if I can do a "test" with a straight fork.

I will post back with any information if anyone is interested.

I'm saying that your Peugeot fork is longer than most any new fork you can buy. Just look at the distance between the tire and the fork crown. They don't make them like that any more. Your fork was made to accomodate 27X1 1/4" tires and still have room for fenders.

It is indeed unusually long in height, as Dirtdrop noted, but it is also long in rake (horizontal projection).