Out on the Interstate

[Purplezinger]

XSJohn (bless his memory) was pretty strong on retarding the timing when re-gearing our 650s to provide stronger, smoother take-off in 1st gear and posted pictures showing how to do it. I put 18T front & 31T rear sprockets on my '82 with stock 16 inch diameter rear wheel and followed his instructions - it worked out to about 5 degrees retard from factory spec. It takes off very smoothly (fairly level ground around here in SE Michigan).

These engines were designed at a time when fuel had a far higher octane number. The super high test at today's pumps would only be regular gas back then. The real reason to retard the ignition when using tall gearing is to prevent knock. The side effect is apparent smoothness. Pinging/knocking/preignition can quickly destroy an engine. High loads at low RPM are a recipe for failure.

 

[Purplezinger]

I'll try to find some links and I could be way off base. I think it's one of those things where there's two beliefs and no real solid answer. One with people saying it's okay to run evens on front and rear and one belief that you should never do that.

ETA: Here ya go...it sorta goes into the even vs. odd thing

http://www.shovelhead.us/forum/showthread.php?t=79998


ETA2: Just google "chain sprockets odd even?"

After reading all the material it appears that odd/even and even/odd sprocket combinations present every tooth to every link eventually. That might make a difference in wear patterns.

 

[Jawknee21]

CAUTION: You will want this everyday. There is no such thing as moderation!
You may find your drive home getting longer and longer.....

Yes. haha. i pass my house just so i can ride longer. haha...

 

[azman857]

I've been known to circle the neighborhood a time or 2 before turning in..

 

[SCHMEEL]

forgot to mention, that its getting oil into the clyinder which in turns is hurting take off.

I bought this bike with aftermarket exhaust with the stock jetting in it. three weeks of tuning and now what I have is a bike that runs great when warm, but untill then the take offs are bad,

 

[Purplezinger]

forgot to mention, that its getting oil into the clyinder which in turns is hurting take off.

I bought this bike with aftermarket exhaust with the stock jetting in it. three weeks of tuning and now what I have is a bike that runs great when warm, but untill then the take offs are bad,

How do you mean the "take offs" are bad? Curious

 

[SCHMEEL]

bogs, hesitates, ^ "twist throttle 1/4 turn it bogs/hesitates/spits/sputters then it will just take off after couple seconds like nothing happened

I'm in the process of aquiring all the components I need for electronic ing. so I havn't bothered messing with the points, vavles, or timing yet. I know I cant complain untill I check out ALL avenues