[jazevedo]

Im going to apologize in advance for this newbie question.
Tomorrow i pick up my Pred, and i was planning on putting the 38 tooth rear sprocket followed shortly by the 13 tooth front one.
However know that 3 teeth in the rear is roughly equal to 1 tooth in the front. So why couldnt i get just the 40t rear from sprocket specialists and use that instead? It would be cheaper and easier changing only the one sprocket instead of both the front and the rear. Has anyone tried this? Is there a reason 13/38 is the prevailing choice for low end power?
Thanks
Jay Azevedo

 

[robg]

The main reason I can think of is that a 40T in the rear with a 14 up front requires a longer chain. Plus, 40 in the rear is three teeth more than the 37, so it's like the 13 up front. But a 13 up front and 38 in the rear is like four teeth in back, so you'd need a 41, and a 41 won't fit without altering or removing the skidplate.

Clear as mud?

Rob

 

[cmc72_2000]

Rob do you definately need a longer chain for a 40t rear and the stock from sprocket? i have a 40 on the way, hope it fits with stock chain.(my 38 seemed to have plenty of slack yet)

 

[preditor-or-prey]

The chain won't fit I tried that.You will have to get a longer chain 3 lengths longer than stock I believe.

 

[cmc72_2000]

that sux does a 39 work w/ stock chain?

 

[jazevedo]

I just got the 13t in the front. I put it on after my break in period. I rode about 5 hours this weekend. (For a grand total of 5 hours on the bike) and my chain stretched so far that i cannot get it into spec tension by tightening it. I am picking up my 38t rear tomorrow, but i still dont know if that will be enough to take out all the slack. My brother thinks i should have a link taken out of the chain. What do you guys think?

 

[sport]

What is the proper 13 tooth sprocket to order and does it need to be machined? Thanks!