Netdewt

So I've had a Specialized Rockhopper sitting in my garage for a while now, not doing much of anything. Would converting it to singlespeed be a good idea for riding in winter?

What parts would you suggest?

iforgotmename

I ride SS in the winter and like it, just make sure to pick the right gearing. If you have a cassette you can use a DMR spacer kit and prob get a good chainline with your existing crank. If not a ss freewheel will work, not sure about getting a good chainline though.

I use the spacer on a cassette method, I am able to get a 2x2 config with the same chain 36x16 and 34x18. 36x16 is a decent all around gear.

ThermionicScott 

I think it's a great idea.



I'm not an expert on Rockhoppers, but if it has vertical dropouts, that would make a fixed-gear/single-speed conversion trickier.

iforgotmename

Is that fixed or ss?

ThermionicScott 

Fixed.

chriskmurray

Nothing wrong with that, they make spacer/tensioner kits that work really well and have all that you need to do it. There may be some trial and error finding the right gear but you can find SS cogs really cheap.

Netdewt

It's a 1996, and has vertical dropouts, grip shifting, 3 chainrings, 8 speed rear cassette. The chain is old. I skimmed this article so I have an idea of how to find the right gears without using a tensioner:
https://www.63xc.com/toddp/halflink.htm

But if that doesn't work, the 4-Jeri tension looks good for cheap. I don't want to bother with fixed on a vertical dropout frame.

Are studded tires pretty much a necessity? Can I stud my old tires myself?

CharlieFree

I would recommend it highly. To avoid re-dishing issues on a low-quality wheel and to do it "properly", I went ahead and built a new wheel using a Surly 135mm hub and utility-grade rim. You can get them in disc/non disc, freewheel/fixed, etc. whatever combination you want. I was lucky in that my old mountain bike frame had horizontal dropouts.

https://surlybikes.com/parts/hubs

fietsbob

I built up a Drum brake Hubset, and used an 'All weather sports' Snow-Cat rims.
Nokian Mount and Ground W tires..

this was early 90's late 70' stumpjumper frame
It still has the 7 by 3 drive-train..

the West is not Flat, like Fargo.

wolfchild

If your bike has vertical dropouts then you will need a chain tensioner, a spacer kit, and few singlespeed cogs. Cheapest good quality tensioners are made by Gusset and DMR. I've used Gusset Bachelor and it's been bulletproof. It's a good idea to remove the 8-9 speed casseete and replace that with a singlespeed cog and few spacers, cassetes aren't really made for SS use because they have little ramps machined for shifting, SS cogs are different. One of my SS conversions is actually a two speed manual shift...38/36 chainrings up front and 16/18 rear cogs, great for winter riding.

Netdewt

So what should I do first? Tear down the bike and see if any cogs/chainrings I have will work without a tensioner?

How many gear inches should I aim for?

Netdewt

Can anyone say whether the Surly or Paul (more expensive) chain tensioners are better for winter use?

iforgotmename

I am running (36x16) 61.5 and (34x18) 51.6 gear inches this winter (I have a 2x2 setup) I ran 66.8 (44x18)last year and didn't have any problems. Although my riding was always on the road without a lot of snow...we had a lighter winter.

My 2x2 allows me to use the same length chain so I don't have to lose the sweet spot for my disc brakes.

Paul is probably going to be better quality but I prefer the single wheel on the surly.

ThermionicScott 

I initially tried 62" (26.1" x 38/16), but that was too much work for the speed I could go on those tires. 58" (26.1" x 38/17) was much better, and I didn't wish for anything higher until I switched back to regular tires.

pyze-guy

Check out nashbar, amazon for single speed kits. Usually about $30, comes with tensioner, several cogs and spacers. Paul is expensive, surly is okay, can't say if they are worth it or not. I used a cheap tensioner and never had an issue.

Netdewt

Still noodling on this.

I bought a recommended wheelbuilding book, and plan to learn. Is an eccentric hub worthwhile @ $185? Or better to just stick with an tesioner on this sort of setup?

ThermionicScott 

$185 is kind of spendy just to avoid using a chain tensioner -- eccentric hubs are more necessary when you're trying to convert a vertical-dropout bike to fixed-gear. I'd just run a chain tensioner, or use your old derailleur as one.