Old Trek Singletrack coaster conversion.

[steve_ohgoodness]

Hello there Mtbr peoples. Long time lerker, first complete bicycle build.
Have an old Trek Singletrack 930 I picked up cheap thats in bad condition. Would like to go coaster ss if possible.
Id like to get any opinions or suggestions.
Thanks!

[fishcreek]

unless it has a horizontal dropout, forget the coaster brake idea.

[locobaylor]

unless it has a horizontal dropout, forget the coaster brake idea.

why? chain tensioner will work fine with it.

[fishcreek]

like a derailleur mounted tensioner? i dont think so, unless you want to die.

[steve_ohgoodness]

I'm currently looking up tensioner options. Anyone know anything about the fitment of these things? Universal? Also anyone recommend a rear wheel? Looking at cruiser bike wheels on Amazon.

[Beatniqwood09]

Pretty sure tensioner wont work.

Magic gear would though!

[steve_ohgoodness]

What won't work with it?
What is magic gear?

[fishcreek]

there are tons of reasons why you should abandon the idea of going coaster brake UNLESS you have a horizontal drops. and i can go all night tell you about it but im pretty sure half of the words used you wont understand. just run a tensioner and v-brake, problem solved.

[Beatniqwood09]

A chain tensioner only applies force opposing the forward direction, so when you attempt to pedal backwards to actuate the coaster brake you'll only end up bending the tensioner back around and dropping the chain rather than stopping.

The only tensioner that might work would be a stiff rigid one that doesnt use a spring

Magic gear:
You can probably find somewhere on the internet(or just measure) the length of your chainstays. Given that number there are a few SS gear ratio options that will fit in verticle dropouts w/o a tensioner

Edit**
Pretty sure there are some other issues with it involving coaster brakes requiring a very specific amount of slack in the chain

I with fish, probably not a good idea

[steve_ohgoodness]

there are tons of reasons why you should abandon the idea of going coaster brake UNLESS you have a horizontal drops. and i can go all night tell you about it but im pretty sure half of the words used you wont understand. just run a tensioner and v-brake, problem solved.

Will definitely be running new set of v brakes. So are you saying a tensioner will or will not work? Thanks for the help.

[steve_ohgoodness]

A chain tensioner only applies force opposing the forward direction, so when you attempt to pedal backwards to actuate the coaster brake you'll only end up bending the tensioner back around and dropping the chain rather than stopping.

The only tensioner that might work would be a stiff rigid one that doesnt use a spring

Magic gear:
You can probably find somewhere on the internet(or just measure) the length of your chainstays. Given that number there are a few SS gear ratio options that will fit in verticle dropouts w/o a tensioner

Edit**
Pretty sure there are some other issues with it involving coaster brakes requiring a very specific amount of slack in the chain

I with fish, probably not a good idea

Great explaination, thank you very much.

[fishcreek]

^thanks for explaining. I agree on most things you said but even running a rigid tensioner will not work. You have to treat coaster like fixed gear condition.

Magic will work BUT keep in mind that coaster hub chainline has no adjustment. So you have to buy an appropriate bottom bracket spindle length to make it work.

So couple hundred bucks later, you can enjoy your coaster bike for few hundred miles until your chain sags. Worth it? No.

[Beatniqwood09]

Some interesting results I found on google. Dont know where to get either of them. But they dont seem like they would be too hard to fab up

[steve_ohgoodness]

Some interesting results I found on google. Dont know where to get either of them. But they dont seem like they would be too hard to fab up

I dig that top one. Also have to address the chain line with the crank as mentioned above. Definitely considering moving on to a different frame because Im wanting a coaster brake bike.

[locobaylor]

I have ran a tensioner successfully on a bike with a coaster brake. I'm telling you, from personal experience, that it can be done and was done successfully. I didn't crash, lose my brake, or drop my chain once.

[steve_ohgoodness]

I have ran a tensioner successfully on a bike with a coaster brake. I'm telling you, from personal experience, that it can be done and was done successfully. I didn't crash, lose my brake, or drop my chain once.

What kind of tensioner did you use?

[locobaylor]

What kind of tensioner did you use?

orgin-8
Products Description – ORIGIN-8

[Beatniqwood09]

I have ran a tensioner successfully on a bike with a coaster brake. I'm telling you, from personal experience, that it can be done and was done successfully. I didn't crash, lose my brake, or drop my chain once.

Pics or it didnt happen...

Just messin... but really

[Andy R]

I dig that top one. Also have to address the chain line with the crank as mentioned above. Definitely considering moving on to a different frame because Im wanting a coaster brake bike.

By the looks of it, you'd have to use a 120mm hub, as the converter plates fit inside the existing dropouts and put up with your frame angles being about one degree steeper.
I'd just get another frame if you're set on the idea.

[steve_ohgoodness]

By the looks of it, you'd have to use a 120mm hub, as the converter plates fit inside the existing dropouts and put up with your frame angles being about one degree steeper.
I'd just get another frame if you're set on the idea.

I'm definitely set on a coaster bike so I'll be looking for a different frame like you suggested. Could anyone recommend a mtn frame with horizantal drop outs? Are old Specialized horizantal by chance?

[Beatniqwood09]

Most older bikes either have vertical or semi-horizontal drops.

The only bikes with true horizontal drops (ie track dropouts) are SS specific frames, OR anything with some sort of sliding/pivoting dropouts (not sure about coaster brake compatibility with sliders can anyone comment on that?)

You could get one of these Save up to 60% off new Mountain Bikes - MTB - Gravity 29 SS Single Speed 29er Mountain Bikes
and then rebuild the back wheel with a coaster

[wjphillips]

I'm curious what the fascination is with coaster brake? I think I haven't ridden a bike with coaster brake since the early 1980's. Does it add some challenge to the trail? Is it somehow mechanically superior to just v brakes? I rode a fixed gear mountain bike off road a couple of times and was pretty challenging. I'm just wondering if coaster brake gives a similar challenge.

[steve_ohgoodness]

I'm curious what the fascination is with coaster brake? I think I haven't ridden a bike with coaster brake since the early 1980's. Does it add some challenge to the trail? Is it somehow mechanically superior to just v brakes? I rode a fixed gear mountain bike off road a couple of times and was pretty challenging. I'm just wondering if coaster brake gives a similar challenge.

For me it's just a nostalgic riding experience.

[Dirty $anchez]

A pre-war Schwinn or the like is the quickest route to your coaster brake dream.

[onecogshortofacluster]

Its just fun.