Cr Ignition - Jetting differences with increased timing?

[dynofox]

Anyone find they needed to fatten their jetting when switching to the cr ignition due to the timing advance?

[derby]

The cr250 ignition lined up the way it should be is really a retard not an advance. You should not see any big changes in jetting. Leave the jetting where it is and start there. You should not be lean if your previous jetting was correct. The higher the rpm the more retard you will get with the cr up until you get to 10 grand. But more than likely (I don't know what setup you are running) you will not hit those kinds of rpm's.

[dynofox]

While doing research before I bought the CR set up I read a few posts from C-Leigh Racing stating with the nonadjustable ESR adapter plate and the CR stator turned as far as it will go to the left (retarding) that it is still advanced 10 degrees over a stock trx ignition.

[derby]

Originally posted by dynofox
While doing research before I bought the CR set up I read a few posts from C-Leigh Racing stating with the nonadjustable ESR adapter plate and the CR stator turned as far as it will go to the left (retarding) that it is still advanced 10 degrees over a stock trx ignition.

Make sure you read it correctly. The stock 250r curve is almost a straight line ranging anywhere from 21-18 degrees of advance depending on which cdi you have. The stock cr250 (set at the tick mark on the plate) will peak at 19 degrees of advance but then the advance decreases as you increase in rpm(up till about 10,000rpm).

I have mapped all of the atc and trx ignitions while also the 99, 00, 01, 02, and 03 cr250 ignitions.

[dynofox]

Originally posted by derby
Make sure you read it correctly. The stock 250r curve is almost a straight line ranging anywhere from 21-18 degrees of advance depending on which cdi you have. The stock cr250 (set at the tick mark on the plate) will peak at 19 degrees of advance but then the advance decreases as you increase in rpm(up till about 10,000rpm).

I have mapped all of the atc and trx ignitions while also the 99, 00, 01, 02, and 03 cr250 ignitions.

Here is an older post of Neil's where the information was found. I have a ESR adapter plate coming for the '00 cr ignition I just bought, the CT plate has not been made in years and is no longer available new (called and confirmed this).


Originally posted by C-LEIGH RACING
Timming adjustments

The ESR plate only has a hole where the bolts go through the plate to mount it to the engine.
The CT plate has slots for more adjustment.
On the CR ignition system, that stator plate has slots on it so adjustments can be made.

What you will find unless by chance some machining changes have been made, the ESR CR ignition adapter plate with only the three holes to mount the plate to the engine, with the CR stator plate itself rotated counter clockwise as far as it will go & locked down the timming will still be advanced around 10* at TDC.
The CT plate with the slots cut into the mounting plate you can retard the timming if need be done.

Neil

[morse250r]

on the cr plate you can removed a few screws and advance or retard the timeing i went fully advanced and picked 7 hp up on the dyno

[machwon]

My information confirms what Derby says. I don't know where that other guys info comes from.

Just did a cr500 on alky with a cr250 ignition today. Slotted the stator plate for more advance and still picked a couple more.