Trav1s

Which wheelset? Vendor? I’m curious about the 650b way…

noglider 

I plan to reverse my conversion. It’s a Lemond road racing bike with titanium frame and carbon fiber fork. The tires are 38mm and a very tight fit in the chain stays, leaving no room for a wheel out of true. Wider would be nicer but they’re impossible here. Handling on the bike is wonky especially if I don’t inflate the front tire just right to 50 psi. Too little or too much makes it bad.

With 700c wheels, it can only take about 27mm in the rear. I might decide the bike just isn’t for me. And I might not.

non-fixie 

The brand is PNA, and is sold by Beastybike, a French supplier. Aimed at keeping all those old French 650B-equiped bikes on the road at a fair price. Their website: beastybike.eu.

seat_boy

That's funny, I just reversed my '84 Trek 610 conversion, and I'm really enjoying it with 700x28mm tires. The bottom bracket was too low with 650Bx38mm, and it just feels snappier and livelier now... though part of that may be a swap to drop bars at the same time.

non-fixie 

I think it is actually possible to enjoy both. Both physically and mentally.

I've also recently converted another bike, from 700 x 28C to 700 x 23C, and I'm really liking the result. On reasonably smooth roads, that is.

noglider 

The bike world has recently learned that wide tires are faster than narrow tires, all other things being equal. (Though all other things cannot actually be equal, but ...) The reason narrow tires feel faster is that they respond more quickly to our steering efforts, and those can be deliberate or passive inputs.

My 650b conversion seems to disagree with the design of the bike. And maybe I don't love bikes designed to be extremely nimble anymore. I notice the happy conversions are of more relaxed bikes. But it did show that wide soft tires are a pleasure. I "converted" my 1971 Raleigh Super Course from 27" to 700c, and it allowed me to use 37mm tires. They are Vittoria Voyager Hyper tires which are out of production. I imagine I'll be able to get equivalent tires when the time comes, but I don't know what they will be. They are terrific tires that ride as if they are lightweight even though they're not.

seat_boy

Yeah, I've read all the BQ stuff about wide tires and flexy frames, etc. But finally, no one is timing my rides, so what feels fun is what's best for me. And right now, that's 700c x 28 (I still have the 650b hanging on a hook for when I want something different in a few months)

brooklyn_bike

another bonus after experimenting with wider tires or as wide as i can stuff in in bikes (42 - 50mm) after 50 / 75 / 100 miles i feel much fresher and less beat. wider tires really help with long fast miles and feeling stronger longer. not that big a deal when i was younger but now as i'm getting longer in the tooth wider tires have been great for longevity

ehcoplex 

A 3Rensho 650B- that's pretty sweet.

noglider 

@seat_boy, I agree. Ride what you like except if there is a reason not to.

I understand how we get shorter as we age: the discs between our vertebrae compress. It seems I've lost a lot of height, perhaps as much as two inches. Do our joints get similarly compressed? From what I'm hearing from older men cyclists, it sounds we are more sensitive to vibration than we used to be.

mountaindave 

I know I’ve lost 3/4” and I’m 50 this year.

I haven’t done a 650b conversion that I don’t like, but I have 700c bikes that I’m not touching because they already ride wonderfully. And with the availability of sewup-quality clinchers to make the ride feel sublime at 28mm (on pavement), there’s no need to fix what ain’t broke.

ehcoplex 

Even the 'good' roads where I live are terrible, and in trying to avoid the inattentive (or often downright hostile-to-cyclists) drivers, many of my regular routes involve gravel stretches- and the 'cushioning' in my joints & spine seems to be deteriorating much faster than I ever would've imagined. Cushy tires are a necessity, and the beauty of a 650B conversion is I can get the ride I need with the vintage steel I love. Here are my two current 650B bikes (actually there's a 3rd, a Trek 400, but I stole it's wheels for the GS build- I've got the rims & hubs for a couple more 650B wheel sets on hand I just need to build 'em up). The PX-10 is what I'd consider 'fully sorted', the GS is still a bit of a work-in-progress. Taped the bars and did a bit of additional chain stay dimpling today for a little more clearance on the 42c tires. Having read somewhere above about someone ( nlerner I think..?) managing to get a Campy GS RD to shift onto a 32t cog I really wanted to give that a shot, but it was no-go, so sticking with the Cyclones. I've got a pair of black, dimpled fenders I can re-raduis from 700 to 650b that I want to put on, but my carpometacarpal joints were not up to it today...

theblackbullet

This bike originally came with 26x2.125" tires and as a 24.3" frame (Trek's official sizing) it looks really odd with the small tires and giant head tube. Since coming into my possession, I've ran 26x2.3" , 700x38 , and now 650x50. The 26" are sure footed on the trails, but feel sluggish on the pavement needed to connect in-town trails. 700c is fast! I still think it's a great combo for a long gravel ride on a dry day. 700x38 has very little clearance with the fork crown. Also it raises the bottom bracket a lot. 650b is really hitting the sweet spot for me. A good compromise for a bike marketed as "all-terrain". I feel confident with this tire on any of the in-town singletrack although I may need to use more finesse going through root-y or technical sections than with the 26x2.3", but the trade off for when I'm on the pavement is worth it.

steine13

Learned Friends:

I need spiritual advice. I had such beautiful plans, but some ugly facts are getting in the way.

The subject here is a 1978 Trek 710 that I bought a couple years ago. It's not mint but close, and it's this year's project bike. The plan is to turn it into a randonneur via 650b conversion. I got a bunch of nifty parts together, both at the co-op and at the April Velo Orange sale.

Not to mention parts obtained through the good offices of folks on this site, be it through purchases or pointing out bikes to rescue and part out. Thanks. I guess. I don't have a problem. I can stop any time.

The following is where I really need help.

I posted this in the bike's own thread (*) but didn't get any responses. You drive-side fetishists all show your perfect bikes, but no gritty details of how the rear fender is made to fit around the chain stay bridge. I'd love to see some examples, hear descriptions, and get advice on how far -- and why -- the fender should dip below the stays. I'm inclined to just use a P clamp and attach it as shown -- but maybe I should dip lower, Dremel and all. Help.



Otherwise, I think the rear fender is going to be OK, especially without a rack.
The front is another matter. But first, a detour.
Success and failure are so close together. Here's something that made me happy as I put on the rear derailleur:



I actually had saved and tagged the nipple for the braze-on. Winning!
No sooner had I installed the cable, though, that I got hit upside the head cuz I didn't pay attention. Hate it when I'm stupid.



Re-seating the housing and adjusting the derailleur clamp was with me the work of a moment.

Given the success of the bar tape under the clamp, I tried the same thing with the front derailleur. This was a serious mistake, because it disturbed the fit, and the clamp broke under light tightening. No pictures, it was too painful. Do Not Do This. I substituted a lesser part, and life went on.

Now: racks and fenders. The rest of this post is mostly whining. Not that I wouldn't like advice, or pictures showing solutions, but I think I'm setting myself up for too much complexity. It's getting crowded up front.

This "jim blackburn" from the Lansing Bike Co-op had all the little spacers with it, which I thought was outstanding work when I bought it. Period correct for the bike, and I even bought a little Rivendell bag for it. Is not this adorable?




Equally adorable are the Honjo fenders, but now things get futzy.
For one thing, the wraparound rack crowds the 559 brakes -- it works fine with the original Suntour side-pulls, but this is tight. Just Lego-ing all the parts together took ten minutes of trial and error.



Nor do I see a happy way to attach the fender bracket. I may have to give up on the rack.



There is not a lot more joy at the lower dropouts. With rack and fenders sharing one 'cheerio', things will get tight. I can already see myself cutting the fender stays fifteen times to get the fender line right..


I don't think this is going to fit.

Two ways I can go here -- either lose the fenders, at which point the rack goes on, I'm setting this thing up with 700x32 GP5000s, and viola.

Or I keep the pretty pretty fenders and go all out with Herse tires -- already in house -- and use it on some brevets.

Anyway, there's my project. Input is welcome, and sorely needed. Don't forget that it was you guys who got me into this.

cheers -mathias

(*) Trek 710 with a story

nlerner

To attach a fender to a brake bridge that’s not drilled, I use a plastic p-clamp:


If I need a spacer, I’ll use a section of wine correct to the appropriate length:

non-fixie 

I'd suggest a (long enough) daruma bolt:



Have a look here: Using a recessed brake bolt or seat post binder for 650B conversion fender attachment at the crown

ehcoplex 

steine13 , my 650B conversions have all been pretty tight at the chain stays, and I've had to dremel the fender end to get things to fit. I usually cut and epoxy some kind of thin aluminum or steel reinforcement to the inside of the fender there to strengthen things, as dremeling off the folded over edge of the fender makes for a very weak point where it's drilled for the bolt that goes to the bridge. I like a nice fender line, so there needs to be a way for the fender to move forward when removing the wheel, so I've done the bit of cork spacer like @nlerner, or used my own version of the 'spring thing' V-O sells. Pre-drilled fenders usually have a 'slot' for the bridge bolt- I try to line things up so that when the fender is in it's 'normal' position, the bolt is at the top of the slot (so when the wheel gets pushed forward for removal the fender kind of gets pushed forward and slightly up), and that dictates how far down it hangs below the stays.

IIRC, on my Trek 400 conversion with Tektro 559 brakes, I had to slightly dimple the fender to clear the brakes. I'm about to head out, but I'll try to get some photos this afternoon.

It's the nature of this whole business to sometimes have to accept that something might not work and a different approach is called for- try to be zen, and turn the frustration into 'part of the fun'.........

rccardr 

Looks to me like that front fender needs to get higher above the tire where it passes under the fork crown and caliper. How much clearance is there between the fender and the bottom of the caliper when closed?
Recently went through a similar situation fitting fenders to larger size tires and wound up relieving the front fender on each side where it passed beneath the fork crown.
Made a lot of difference in both fit and fender line.

base2 

This is what I love about this forum. I had to Google image search until how this thing worked until I understood it fit inside the fork crown from the underside and suspended from the brake bolt. I never would've come up with that on my own. Fantastic bit-o-knowledge right there. Thanks!

ehcoplex 

I've had a couple installations where the tire-fender-fork crown clearance has been pretty tight so to gain a few extra mm I've used one of these couplers (dremeled down) with a daruma (also trimmed down), so I can use a cap-head bolt from underneath the secure the fender. I uses a bit of lock-tite on the daruma/coupler connection.



A little fussy, requires some trial and error to get the lengths all right, and probably kind of silly just to gain a couple mm.. Maybe better/easier to just rivet/bolt one of these to the fender in the right spot...

Here are a some details of the 'spring thing' and the epoxied reinforcement (please excuse the dirt...):




And finally, if you haven't already found it, there's a wealth of knowledge about fitting fenders in this blog series...

steine13

Learned Friends:

These responses are exactly the sort of thing I was looking for. @nlerner's closeups clarified things quite a bit, and I even found a proper-sized P clamp in my hardware box. Given the company I keep, corks should be easy to come by

I was as puzzled as @base2 by @non-fixie 's daruma bolt. Thanks for the clarificaton, that looks like a useful piece of kit.

"Try to be zen" - right. Totally a strength of mine. @ehcoplex got the emoji's right. And thanks for those pictures as well.
@rccardr wrote "Looks to me like that front fender needs to get higher above the tire" -- I should have been clearer -- I just laid the fender on the tire, for a rough visual idea. The 700 series Trek was a reasonably sporty bike, originally intended for 700c, not 27", so the distances are not too goofy, and I might be able to just use the Honjo hardware with a few mm of leather or inner-tube spacer.

I did get the rack mounted, which was not as straightforward as I would have thought. It was difficult to line up the bolt with the threads, but now it is on securely, without buggering anything up. Some days, that counts as a win.

There's a 200k brevet this weekend, and I'm watching the weather. I can get the fenders done -- OR I can ride my bike, but not both. I'd prefer to ride, and I'll decide what to do when it's clear how badly the fenders would be needed.

But no matter when I put this together, I now have something akin to a plan.

cheers -mathias