suntour screw on freewheel

[delfinis38]

Hiya chaps... i'm hopping someone can offer me some advice on vintage suntour freewheels. my old mountain bike a specilized rockhopper (mid 90's vintage) has done many many miles and the free wheel has seized, and the wheel no longer runs true.

I've finally found a suntour screw on 7 speed free wheel cassette on ebay and i now need to buy a new rear wheel to fit it on. will this cassette fit on any screw on rear hub or do the screw thread / pitches vary between manufactres thanks for any advice.

I was thinking if buying a cheap quando screw on hub to fit the suntour screw on 7 speed cassette on.

thanks for any advice.

 

[Globalti]

Why Suntour? I know their stuff is good (love their thumbshifters) but if you really need a new wheel (why do you?) this would be an opportunity for you to go for a Shimano cassette on a splined freehub, a more modern arrangement easily changed with a small cassette cracker tool.

 

[delfinis38]

thanks for the reply... why suntour... well the rest of the bike's drive train is suntour and if i changed to shimarno as you suggest it would mean changing the front crank too and the rest of the chain set. I've tried mixing and matching with a rear shimarno cassette and the teeth pitch are different to the rest of the suntour stuff.

I would like to do as you suggest and change to a more modern arrangement. but to be honest with you if I'm into spending lots of money on the bike. I'd rather put the money towards a new modern mountain bike. As this bike is my old messing about bike i was hoping to fix it fairly cheaply hence the question about suntour bits. and whether this new suntour screw on freewheel that i bought for three squid would fit onto any screw on rear wheel in particular a cheap quando one.

thanks for any advice

 

[MartinC]

The Suntour block will screw on to the Quando hub - the hub thread is a universal standard (apart from really obscure old stuff from before we were born). But you could get a new 7 speed freehub. I think Shimano 7 speed cassette spacing is the same as SunTour Accushift 7 speed (check http://sheldonbrown.com/k7.html). You can then just change the rear wheel to a freehub, get a Shimano 7 speed cassette and keep all your other SunTour bits.

 

[delfinis38]

martin many thanks for your comments, you have been most helpful. do i require any other bits apart from the suntour screw on free wheel and the new quando wheel to make it work. would you recommend putting a plastic protector disc behind the free wheel.

 

[Amanda P]

Chiming in for a minute, you say the wheel doesn't run true. If you're aiming to get the bike working again without too much cost, you may very well be able to get the wheel trued good as new - if it's not actually Pringled, it's probably a straightforward job for any decent bike shop mechanic.

Then all you need is the freewheel.

I'm also surprised to hear you say that Suntour gear has different tooth pitches to Shimano. I've never heard that before, I don't believe it's true. If you had problems in the past, could it have been that you used an old chain with a new freewheel and chainrings, or vice versa, and it skipped about? That's quite a different problem.

Anyway, as Martin says, if you're determined to replace the wheel, now's the time to switch to a freehub/cassette setup.

 

[MartinC]

Definis38, just looked at Sheldon Brown properly. The SunTour Cassette spacing is a bit weird - some sprockets are 4.8mm apart and some 5mm. Shimano 7 speed spacing is 5mm. It's close enough that it might work, but it might not work well enough.

So using the ebay freewheel is a safe option. Apart from the new hub (in a wheel!) and the freewheel you don't need anything else. Plastic disks are a great cause of controversy - some say they aren't needed, some say they could stop the rear mech catching the spokes and breaking mech, wheel and frame if the mech is knocked or badly adjusted. If you don't mind how it looks then the disk can't possibly do any harm.

Couple of points:

- put some (a smear) grease on the threads before you assemble
- do it up tight (with a chain whip if you've got one) before you adjust the gears otherwise the pedalling pressure will tighten it up and can put your adjustment off
- you'll need the correct remover if you ever want to take it off again, from memory it'll be a 4 dog one.

 

[delfinis38]

martin thanks for the reply again. as you say the shimarno spacing is very slightly different from the suntour and it's the safer option. I've actually tried it with a shimarno cassette it works okay ish... but it's not a smooth transmission and you certainly would not want to cycle any distance on it.

I've bought one of these suntour power flo free wheels and it's a two pin key to remove it when the need arises. I don't have a chain whip so was just going to find a nice big hill to cycle up to torque it up.

once again many thanks for you advice.