sheerider1026 Posted October 28, 2007 Report Posted October 28, 2007 68mm bore stock stroke, 20cc domes on 93 pump gas, what should the timing be set at? i am at +4 but have heard the cubs get a lot of timing advance?? and ideas? Quote
Handyman Posted October 28, 2007 Report Posted October 28, 2007 68mm bore stock stroke, 20cc domes on 93 pump gas, what should the timing be set at? i am at +4 but have heard the cubs get a lot of timing advance?? and ideas? I'd stay at +4 if it runs good. Heard anything more than +9 is not good Quote
dajogejr Posted October 28, 2007 Report Posted October 28, 2007 I'd stay at +4 if it runs good. Heard anything more than +9 is not good Not true at all. A few questions that need answers before I give you my recommendations.. How and where do you ride? Dune for a long time, or just drag race, shut it down, cool it off. Do you want to run pump gas or do you mind running race fuel?? IF you dune a lot and want to run pump gas, leave it. If you want to dune and run race fuel, bump it to 6. If you only drag race and want to run pump fuel, and give it ample time to cool down after 1 or 2 runs, max the plate out at 10 or 11. You must be sure your jetting is on after doing this...if it's borderline or lean, it will melt in a quick hurry... So, I'd go a jet or two on the rich side before putting this much timing in it. On my 4 mil cub on gas last year, I had a dyna set on the most advanced curve...AND 8 or 9 on my plate. I duned it, drag raced it...etc. I had 185PSI or so and ran 110. That bike ripped all year and the pistons looked awesome when I tore it down at the end of the year (to build bigger). However, I'm a fanatic about checking plugs and I always make sure it has plenty of fuel.... Quote
sheerider1026 Posted October 28, 2007 Author Report Posted October 28, 2007 i trail ride and play.. ido drag some also .. i always runs my bike on the righ side.. actually too rich. i was wondering if i could go up to like 7 on it?? its really hard trail riding this bike.. i am debating to going back to a stock cylinder setup.. been running the cpi pipes(inframes) but might tryo to put my t5's back on it?? not sure.. its not as snappy as i would like it to be either Quote
dajogejr Posted October 28, 2007 Report Posted October 28, 2007 i trail ride and play.. ido drag some also .. i always runs my bike on the righ side.. actually too rich. i was wondering if i could go up to like 7 on it?? its really hard trail riding this bike.. i am debating to going back to a stock cylinder setup.. been running the cpi pipes(inframes) but might tryo to put my t5's back on it?? not sure.. its not as snappy as i would like it to be either Putting T5s on a cub is like putting a muffler on a top fuel dragster...don't do it. I had stock carbs and T5s on my 4 mil cub while pipes and carbs were ordered. It still had too much of the wrong kind of power. Cubs are NOT trail machines. NO amount of timing or compression is going to change that...trust me, I ran a bunch of both. Duning and drag racing...perfect. Trails, NO. I don't know what you mean by snappy... By lack of power and torque in lower RPMs...if that's what you mean...then yes, you will never get that out of a cub. They are designed with drag porting, period. Nothing down low....nothing in the middle..than a hellacious top end pull that just keeps on going. You can't make this motor something it's not... Stock cylinders with a good port job will be 100% better for trails and light duning. For occasional duning and drag racing, these are the cylinders to have. What length swinger are you running by the way?? Quote
sheerider1026 Posted October 28, 2007 Author Report Posted October 28, 2007 a +4 which i put on when i put the cub motor on.. i am taking the +4 off and going with my +2 which i like a hell of a lot better.. so do u have any suggestions on what kind of portwork to have done to a set of stock cylinders... i ran a set of stock jugs with no port work and all the bolt ons ( head, timing t5's, stock carbs, vforce) and i really loved it, it could have used a little more top end power but i loved the low-mid snap that it had also.. what do u think? Quote
jbooker82 Posted October 29, 2007 Report Posted October 29, 2007 so do u have any suggestions on what kind of portwork to have done to a set of stock cylinders... i ran a set of stock jugs with no port work and all the bolt ons ( head, timing t5's, stock carbs, vforce) and i really loved it, it could have used a little more top end power but i loved the low-mid snap that it had also.. what do u think? Probably a play / dune port job. Getting your stock cylinders ported is a 100% improvement over stock porting. Why not throw in a 4 mill crank? Your port job is going to cost the same weather it is for a stock stroke crank or a 4mill crank. You will need a cool head and run stroker domes though. Quote
sheerider1026 Posted October 29, 2007 Author Report Posted October 29, 2007 how much better would the 4 mil run over the stock stroke?? is it worth the money and work?? if so i have a like new hotrods crank.., has 5 rides on it also.. what difference is noticed going from a stock stroke to a 4mil? Quote
J-Madd Posted October 30, 2007 Report Posted October 30, 2007 how much better would the 4 mil run over the stock stroke?? is it worth the money and work?? if so i have a like new hotrods crank.., has 5 rides on it also.. what difference is noticed going from a stock stroke to a 4mil? Nght and day.....at least on the Cub. I have a motor like yours and a 4mil Cub. Probably only about 3 tenths or so difference in 300 ft, but the 4 mil pulls 10 times harder it seems. I've ran +9 timing on my Cub, but I think its back at +7 right now. It was getting hot quicker than I'd like. Quote
Animalman294 Posted October 31, 2007 Report Posted October 31, 2007 Yeah, I really like my 4 mil cub, and going to be putting either CPI's or Shearer's on it haven't decided yet, and 39 carbs instead of the 35's......... It runs really good now but after that it will run like a raped ape. First I need to change the coil and ignition I think............... Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.