Bklyn

I'm looking to convert this 1982 Fuji 12-speed to a singlespeed for the winter. It's in pretty good shape. (It was my dad's. He rode it for a single summer. It sat in the garage for 25 years. The gum brake hoods didn't make it, but everything else seems fine.)
Here are my questions.

1. The spacing in the rear is 130, if I'm measuring right. Will I have trouble finding a rear wheel?

2. The chainring is funky. Instead of the inner ring being attached directly to the cranks and the outer ring bolted on, this seems to be the opposite. (See the pictures; hard to explain.) The outer has 52 teeth, which is huge, right? The inner is 42, which doesn't seem ideal, either. Does it look to you that I can bolt on a 46t chainring and keep these cranks?

3. How weird would it be to keep the 27" front wheel for now and ride on a 700 rear until I have the money for a new front?

4. And looking at this bike, is it worth converting at all?

jet sanchEz

I built a conversion and I liked it but I liked it so much that I went and got a track frame and now the conversion frame is a SS frame. Had I the choice to do it all over again, I would still go with a conversion first but only because I am a bike nut and had all the parts to do a SS and a fixie; most people don't have a garage full of crap like I do.

Is that bike worth converting? Sure. I'd get a decent rear wheel that you can use in the future and just space it out. The rear spacing is 120mm for a track frame so just use some thick washers to make up the 10mm, that is what I did. The only money I would spend for now is on a rear wheel, use the 42 crank if you can, that is a fine size to start with, get a 15t cog for the rear and you are cool.

My conversion and track bike are in my signature if you are interested.

sers

1) not if you go to www.irocycle.com
2) no - read up on cottered cranks
3) instant gratification?
4) depends on what are you looking to get out of it, what parts you have on hand, and what tools you have.

Bklyn

Thanks for the replies:

SanchEz: If I use the 42 ring, that makes the 52t ring a kind of chainguard, then, right? I don't think I can just remove the big ring.... (Your conversion is pretty amazing-looking. Kind of unreal....)

Sers: I don't think these are cottered cranks; that's just a dust cap, no? There are no pins. The photos aren't great, I know....

jet sanchEz

Yeah, I suppose that the big ring could act as a chainguard. Since you have that extra 10mm of space to play with, you should be able to get a nice straight chainline as well by adjusting the spacers. For example, on my conversion, I had 126mm of room for my 120mm hub. I had 2 spacers on the non-drive side and 1 spacer on the drive side, making a perfect chainline for the cranks that I was running.

crankstar

I have cranks like that on a old bike, they are not cottered cranks. The big ring and the crank arm are one piece. I would remove the inner ring and just use a bigger cog in the back. Just get a cheap 700c rear wheel you wont notice a difference with a 27'' up front (you can use different size tires a 23mm up front and 28mm in back to even it out). Looks like an easy conversion.

sivat

Like crankstar said, 52t is only huge if you run a small cog. If you run a 18t cog, its not that big at all. If you've got a lot of hills to deal with, you can even go for a 19 or 20t. The only problem with using the outer ring is chainline. You can measure to see what it is. You want to be as close to 42mm as possible, though you can go up to about 47mm without any real problem. If the chainline is off you can either look for a different length bottom bracket, or use the inner ring. As someone else said, 42t isn't bad. I run 42/16 (I have bad knees) and many people run 42/15.

I agree with the advice on getting a wheel from IRO. Have them space it to 130mm and if you change frames someday, its easy to remove the spacers to get to 120mm.

Other than that, the frame looks cool. Does it have a tubing sticker?

Aeroplane

Crankstar is totally right. Just take off the 42 and run a big cog (19 or 20t). IRO will get you a repaced wheel, and you can adjust the spacers to deal with your chainline. Nice and easy.

hankNYC

Hey Bklyn,

Just finished my own first not too long ago and wrote up this photo description...hope it helps save $ and avoid mistakes.

https://www.jaycokingpin.com/singlefix.pdf

jyossarian

Leave the dork disk on if you can. It'd drive roadies insane.

piratically

leave the 52 on. my conversion is 52x18 which is pretty much perfect for me, even up hills.

poopncow

time out, there is a potential construction issue with these cranks.
there was postings a while back that the large chainring is threaded onto the drive side crank arm.
Risk is that it will unscrew after repeated application of back pressure (skids)

poopncow

bikes of that era had 125/6 spacing, recommend remeasure with rear wheel removed

there were a dozen threads concerning questions with convert 27" bikes to 700c last week

lunacycle

That bike is an excellent candidate for singlespeed conversion.

If you just want to convert this to a singlespeed, but not fixed-gear, then it's a very simple matter:

1. Remove the rear freewheel cluster using a freewheel remover (and probably a bench vise) -- Your bike does not have a cassette, so the freewheel screws on to the hub.
2. Screw on a new 3/32" bmx freewheel -- maybe a 19t. 52x19 is a really nice gear.
3. Remove the shifters, derailleurs, and the inner chainring.
4. Shorthen your chain.
5. Tighten the crap out of the rear quick release skewer.
6. Ride your bike.

Total cost should be under $20 (assuming you already have the required tools)

Your chainline will be way off, but for a winter beater, who really cares? If you really love singlespeeding (and you probably will) then you can always spring for a new wheelset -- fixed / free, or whatever, but you'll probably need a new crankset to get a better chainline.

kemmer

You could grind down the teeth of the big ring so it doesn't snag your pants/shoelaces too.

Bklyn

Wowee. Are you a Zen master of good vibes or something? That sounds just great. That's my project this weekend. And as long as the cranks are off, can anybody recommend good grease to repack a 25-year-old bottom bracket?

Bklyn

One thought, though: Will I have to redish the wheel?

roughrider504

If you keep the axle spaced for a freewheel, you dont have to. But the chainline will be off.

If you want a good chainline, you have to respace the axle washers and respace the wheel.

Aeroplane

If you mess with the spacers on the axle: probably. It shouldn't be that big of a deal though.

sivat

The phil woods bearing grease is the cadillac of greases, but really, the $5 tub-o-bearing grease you find at an autoparts store will also work.

peripatetic

Bklyn,

I've done several ss conversions of the exact type you're attempting. PM me if you'd like some help, I live in Williamsburg, go to school by Borough Hall. I also have any tools you might need. Re-spacing and re-dishing are way easier in practice than in description.

Quick tip: before working, go by your LBS (recycle-a-bike in DUMBO's good, there's also a good shop on Atlantic, in Boerum Hill) and ask for a variety of axle spacers--1, 2, 3 mm. It's really annoying if you can't get the spacing just right once you're at that stage.

Bklyn

Peripatetic: Thanks for your offer. I've got a great LBS in Manhattan, and I'm getting the mech there to redish the wheel (and also to give the bike a once-over -- it is 25 years old, after all). My one worry: They only had an 18t freewheel. Is 52x18 crazy? I really don't know; seems to me it's only one off of 52x19 -- how big a difference could there be? But it's pretty cheap, and if it proves too heavy, I guess it's easy enough to swap it our for a 19t or 20t. I'm really looking forward to this. Thanks, everyone, for your help.

Redrom

I have the exact same bike, but in black, and am about to begin converting. After looking at the bike my LBS recommended going with the inner ring because it would give a better chainline. I like the idea of using the outer ring as a chain guard because the cranks have "Fuji" on them, and want to keep that.

What's the cheapest price for a fixed rear wheel (or what's a fair price used)? Are there methods for using the old wheel for fixed? Why not get a fixed 27" rear wheel?

mattface 

52:18 is great