Rear wheel conversion.

General Help
1

I am currently building a 27inch frame up using an old screw on cluster type rear wheel. I have scored a Dicta free wheel to use but have realised that the chainline is way to close to the BB shell of the frame to even consider being able to mount a crank :expressionless: I have noticed afew other 27 inch build ups on here and am just wondering a) how have other people solved the problem? and
b) is there any other type of freewheel conversion kit available for screw on type hubs?
I am making this bike as a single speed, not fixed gear. Any help/advice greatly appreciated

2

pics might help? not sure if i understand the problem. Have you spaced the rear wheel? tried putting the ring on the inside of the crank?

3

If you’re only gonna single speed it then leave the multi speed freewheel on and run a chain straight back. Leaves little in the way of gearing options but if you run the smaller ring on the outside you might be able to roll OK with say a 42 x 14 or 15 (which is where it usually falls). No dishing, no extra cogs, no work other than stripping derailleurs and cutting the chain short.

Ghetto singlespeed :wink: 15 minutes max !!! extra cost = $0

4

If you’re only gonna single speed it then leave the multi speed freewheel on and run a chain straight back. Leaves little in the way of gearing options but if you run the smaller ring on the outside you might be able to roll OK with say a 42 x 14 or 15 (which is where it usually falls). No dishing, no extra cogs, no work other than stripping derailleurs and cutting the chain short

Only trouble with that option is I threw away the rear cassette before I realised the problem :oops:, though I could just sort another rear cassette.

pics might help? not sure if i understand the problem. Have you spaced the rear wheel? tried putting the ring on the inside of the crank?


Basically I need to move the chain line away from the hub. I already have the chain ring on the inside of the crank.

5

Just to clarify, the problem isn’t that you’ve got a 27" frame, it’s to do with the fact that your rear hub is designed to be used with a screw-on cassette, not a single speed freewheel.

In your photo above, you can see just to the right of the freewheel there is a spacer (they’re usually around about 15mm long, or thereabouts) between the freewheel and the right hand locking nut on the hub.

I can think of two (or maybe three) possible solutions, in order of ease and cost:

  1. spirito nailed it on the head. I know you’ve thrown away your original screw-on cassette, but old ones are really easily available. Try hard rubbish, or bike shops (they usually have a couple of old bikes that they use for spares). As was said previously, it’s cheap, it works, and you can put the chain on one of the smaller gears to get an appropriate chainline (then you can change the chainring at the front to get desired ratio).

  2. If you’re planning on keeping this bike for a while, you can get a new rear 27" wheel with a track hub that has what looks to be 130mm spacing. They’re pretty affordable, and most shops can order you one from Bike Solutions (or similar). This way you get to use your freewheel, and it will make your bike look a little more finished, although it’s obviously going to cost more.

  3. If the wheel has a really special rim that you were saving for a rainy day (today being your rainy day) and don’t want to have to have mismatched rims, you can get your current rim relaced to a 130mm track hub, which will also mean that you can use your Dicta freewheel, and that you’ll have much better chain line. It’s the same option as above, except you get to use your existing rim. It’s expensive, and unless you were really keen on using that particular rim, I probably wouldn’t bother.

Just my 2c.

6

That 15mm spacer.

Move the spacer on the axle to the other side of the axle. And then tighten up the cones and your spacing should be fine. I have done it.

This will make the wheel more dished to one side, so you will have to shift the wheel from the right (looking at the back of the bike) to the left. So with a spoke key, loosen the right hand side nipples and tighten the left ones. Do all of one side then move on to the other side.

I will put some pics up if you need some clarification.

7

Moving the spacer won’t change the dish, but it will offset the whole rear wheel. And tightening the cones? I didn’t think we were talking about bearing adjustment here.

If the chain line is that bad - and the definition of ‘that bad’ is the chain doesn’t feed onto the chainring properly and falls off - just get the wheel re-dished/spaced - I think this is what Boofa meant.

If the chainline is servicable but you are worried about it, you can get a small chain guide - I think Pauls Comp make discrete ones.

8

Have you already re-dished the wheel? If not that chain line should be about equivalent to the largest / second largest gear on the cluster which should have a fine chain line to an inside chainwheel?

In the past I’ve cut those spacers in half - moved one half to the non drive side an then slightly re-dished (tighten non-drive side spokes) to centre the wheel - you could try that? It will five you an extra 80mm or so of chain line which might get you over the line.

9

Ah yes, I meant moving the spacer to the other side, and re dishing the wheel.

Late night, does things to you.

10

Cheers for all the replies, I now have some information to help me solve the problem. Will keep you posted :slight_smile:

11

Check out Bob’s Garage chapters 5, 6 and 7

He’s put together an instruction video with pics on how to work out your chainline, then respace and redish your hub. It’s what I used when I converted an old 27" frame

12

^ he’s the man!
But what happened to the rest of the videos, he never finished the bike :frowning:

13

Just watch the dismantling the bike vids in reverse :stuck_out_tongue:

… don’t forget the beers … very important tool in the workshop

14

not to change the topic, but what are those dropouts?? Are they green?

15

bonsch, yes they are green! I painted the lugs and dropouts green. :smiley:

http://fixed.org.au/forums/index.php/topic,8974.0.html
Should explain all

16

man, i love that… Never really been a fan of all chrome frames, but looks awesome with a bit of colour on the lugs and dropouts! :stuck_out_tongue:

17

lets try and keep this clear.

  1. Go to local bike shop and beg or buy a colection of spacers. Any decent bike shop will have a junk bin filled with hundreds of those suckers in various lengths.
  2. Use spacer combination to get a reasonale chain line to inner or outer ring
  3. You now have a bike that is kinda rideable but the wheel is off center because of the dish to accomodate the old cluster. ride for a while if you like
  4. Redish wheel to bring tyre back to center . Painful job but doable at home. You now have a rideable bike for a short period of time before the spokes start to go ping because of the change in stress angles and the old spokes being cracked
  5. Respoke the wheel and franklely I would do this rather than redish the wheel as in 4
  6. if you are respoking consider new hub and or rim depending on state of old

hope this helps

18

^ or just buy a rear track wheel to begin with :wink:

19

Thanks all for the help. Have a mate who used to manage a bike shop so he is going to help me out with redishing the wheel. Am trying to do this on the cheap as the fixed I am building is costing lots of money. Will let you know how I go :smiley:

20

Sorry for the gravedigging.

I’m having the exact same problem with the original wheel but don’t want to use a six speed cluster.
Will this solve my problem?

Conversion Kit Fixie Bike Single Speed Shimano Adaptor | eBay