i have fitted my 70s kit with laser exhaust system.. i had the standard rollers in there with a 60 jet i had it running on a 30-1 premix with oil line still connected which i got told to do .. it struggled to get to 30mph.. so i changed the rollers to 4.6g and it reved alot till 15mph the the revs dropped and picked back up till 35mph.. i then put 3 standard rollers in with 3 4.6g rollers and it runs like shit so i have put the standard jet back in there and put the standard rollers bk in and it struggles all the way to 30mph again can anyone help me please as i need the bike ready for the weekend so i can get to work next week
Jetting should be done first... then you move on to the rollers. Dont put your standard jet back in as ou need to upjet from the standard with a 70. You ll be running lean which isnt a good thing. What s the weight of the standard rollers?... and what bike is it?
ok ill changed the jet back asap the standard one is a 47.5 and i have a 60 is this ok or to big ?? im unsure of the standard rollers weights as there is nothing on them and i dont have any scales i know most of u might laugh but the bike is a generic cracker it was jus a cheap project through the winter ill sell it n get a rox once it running right
Cant really tell youn what size should be used as it differs from one engine to another. Need to try it to be honest, but be sure to start with slighly bigger ones and go down in size (5 by 5). Can you feel a difference? You need to drop some weight from the standard ones. Again, only tests will give you an exact answer. Mixing weights is only good as well for tunning, be sure not to keep them in there in the long run. You could do a bit of research online and see if you can find the weight for the standard rolls for your ped. that wuold bhelp you for a start as you culd be playing with the wrong rolls...
ok well the only site i found that tells me says my bike has a malossi variator standard with 16 x 13 rollers which is a lie as the rollers r 15 x 12 lol ill ring the mother and see if he has any decent scales ill weigh them up and buy some 1 gram lighter ?? iv seen alot of people sayin bout clutch spring and the spring behind the clutch aswell ? also wat colour should the spark plug be ??
1 gram lighter for a start would be fine, and you could mix them for testing if needed. I wouldnt touch the clutch for the time being. As I said before jetting and rollers are first. The plug should be a nice brown in colour.
thats good then lol its a slight brown colour atm lol how do i know if the jet im usin is to big or to small
You shoud be able to open full throttle from the start without the ped bogging first (with a brown spark plug only as you can still do it running lean but SP would be white..ish)... There quite a few detailled jetting thread all over the internet
What you do is go full throttle and go for few hundred meters (not miles!!!) and cut the engine. Look at the plug.. if brown it s good, if white you are running lean and need a bigger main jet, black your running rich and need a smaller one. Main jet done first, then need and finally air screw/secondary jet. Once jetted correctly you can do the rollers as you would not want to run lean when trying to tune your rollers
secondary jet is only ever changed for fine tuning to be honest, dont really need to look at it just now.
ok ive been looking about online and its confusin the shit out of me lol i think it gunna b easier if i pay my local garage n get him to get it on the dyno and sort it out for me
