Jetting CR500

[BigSwole]

Had two very good riders tell me that my 500 wants to lay down on the top end.They said to check my jetting.I dont know anything about jetting it and they were short on time and had to run.any help on how to do it and what jets I should be running? I'm at Elavation 2900 and running 40:1 mix The bike has very low hours and they also said it was very good on the bottom end and midrange power wise.so what do you think?what kinda jets should I be running.also the bike sat for awhile and came out of Calif.thanks for any and all info.

 

[chaostheory]

i have an 85 cr500 and it is very strong on the low and midrange but mellows out on the top end, not sure if its a trait of these bike or we just need proper jetting,
My engine mods consist of a boyesen rad valve and a pro circuit platinum pipe and factory sound silencer i also converted to 91-01 plastics, subframe, airbox, im running mc-1 at 50:1 ratio.
according to boysen i need to go one or two sizes smaller on the main jet but i havnt changed anything because it performs so well in the rpm range i ride most of the time
Also, it would also be a good idea to get a honda service manuel, you can get them on auctions sites for cheap and it contains almost all the information you need for tuning and jetting your bike

 

[gowen]

More than likely they were used to a KX500 which has powervalves and are much better in the high rpm range. I had a cr for a bit and it was the same, did not make much to any at top, but the hit was in the low to mid range.

 

[500_boy]

Hey chaos, I was wondering where you picked up your boyesen Rad valve. I cant find one for my 85 CR. Also was it alot of work switching to them 91-01 plastics and airbox. I am looking at doing the exact same thing so I can get a nice looking graphics kit. Thanks.

 

[bigcr]

The best way to get more top out of the CR500 is through porting and boring the carb.