Bicycle Mechanics - 6 Speed fix up

I have an old mountain bike that I putting back in service. The rear wheel is a six speed with a non quick release hub. I noticed that the rear axel is bent, so that will have to be replaced. Also the rear deraileur, which is an older model Deore, is broken at one of the pivot points, so that will have to be replaced too. My questions are:
Can I put a quick release axle in place the bolt on type that is there.
Will a newer derailure such as Shimano Deore LX work with the six speed.
Would a newer 8 or nine speed rear wheel fit between the drops on this frame.


Thanks,

Don

You may be able to substitute a QR axle, if you replace the cones and locknuts, as well. I have done the same thing on older road hubs. [If I recall correctly, solid axles have a slightly smaller outside diameter than QRs.]

Assuming you have a standard-width 6-speed freewheel, you can freely substitute a 7-speed, which is only about a mm or so wider, particularly if you remove the spoke protector.

Replace the chain if it has elongated by more than 1/16 inch per 12-inch span.

If you stay with friction shifting, as I would, you can put on almost any wide-range rear derailleur.

Around '90 and '91 the six speed standard for dropouts were 130mm. The current is 135mm.

Also the current Shimano derailleurs are backwards compatible. The current ders will work on earlier indexing.

Thanks for the replies. The chain is new. The cones show some wear so replacing them is probably a good idea. Can I get the loose bearings at a bike shop? The shifters are Shimano Deore indexed with a friction option, so it sounds like I should be able to make almost any new derailleur work.
Now what do about that U-brake mounted to the bottom chainstays?

If you want to fix your set up you will need a new axle. Shops will sell you this complete with cones and all.

You may also want to look at a new rear hub or wheel. Many times a complete rear wheel is very inexpensive and much better solution in the long term.

Derailleur you can use any Shimano out there.

Buying a new rear wheel/hub may end up being 7 or 8 speed. In this case you will also need a new cassette. Shifter will still work if you run in friction mode.

U Brake - You are stuck with that. Lube the posts and clean cable routing on BB shell to smooth it out a bit.

Originally posted by DonTx
...Will a newer derailure such as Shimano Deore LX work with the six speed.

If and when you buy the derailleur make sure you verify the type of attachment to the frame. Many MTBs with nutted axles have an adaptor claw instead of a dropout:

http://www.sheldonbrown.com/gloss_a.html#adaptor

Take the old derailleur to the shop with you if you are unsure.


Would a newer 8 or nine speed rear wheel fit between the drops on this frame.

Not as such but you may be able to manipulate the frame to accomodate it if the frame is steel.

http://www.sheldonbrown.com/gloss_sp-ss.html#spacing

Bear in mind that you have a freewheel rear hub and 8/9 speed hubs are of the freehub type so don't think that you can change to 8/9 speed easily later. Also, I am not sure that your shifters can pull enough cable for 8/9 speed. If you can get the cones and axle cheap then by all means fix the hub and perhaps add the 7-speed freewheel as was suggested above. I would not bother with trying to convert the axle to the QR type. Unlike the nutted type, the axle length has to be precise as the axle cannot extend past the outside of the frame and the length you need might be unavailable.

Don't spend more money than the bike warrants as this becomes a slippery slope and you will quickly be spending more than what a brand new wheel would have cost. Also note that freewheel-type hubs such as yours are very prone to having the axles bend and snap so the situation will likely repeat itself.

http://www.sheldonbrown.com/k7.html

I would suggest looking for a used 7-speed wheel (freehub/cassette type) which someone is selling: it should be cheap, it will be QR, axles rarely bend with this newer design, your frame (assuming it is steel) will accomodate it more easily than 8/9 and you should still be able to get a wide range of cassettes for it.

As for the brakes, you could have cantilever posts brazed onto the frame (again, assuming that it is steel) but this would probably be more trouble than it's worth. U-brakes aren't terrible (except for the location) and the front brakes are more important anyway.

Do not worry about the chainstay-mounted U-brake. I have one on my 1988 Schwinn mountain bike, and although it is admittedly mounted in an incredibly dumb location, it has given me years of trouble-free, effective braking. It also protects you against chain suck (see chain suck thread in this forum).

I notice also that chainstay-mounted U-brakes are making a comeback among the BMX crowd.

Just to update and to say thanks again:

The frame is steel, the reason I am reviving this bike is because of the frame. It is heavy and durable and has braze-ons for front and rear racks, two bottle cages, and spare spokes mounted to the chainstay, as well as plenty of room for fenders. The intent is to make this my grocery getter and knock around town bike. Therefore if I can find a cheap seven speed rear wheel I will go with it otherwise I will get an axle. As for the Deraillure I will probably go with a basic new Deore plain long cage rear unless something else comes up.

Happy riding