jetting help

[707trx250r]

I Just got my R back togeather, a new top end. On the new motor I raised the compression and am running straight VP C-12.
I was wondering if I need to richen or lean my pump gas jetting. I am going towards leaning by how it is running.


Thanks for looking and for the help!

[1988R]

Jetting questions are hard enough to answer on the comp. without actually being there but with the amount of info your giving us its impossible

[707trx250r]

sorry about the lack of info.

I have an 87 r.
It has-
Rad valve
paul turner midrange pipe + fat boy
stock carb
67 mm wiseco piston
reed spacer
Br9es plug
cr head gasget
and mid range porting.

I also live in the bay area, so low altitude.

I should have put this in when I became a member.
Thanks

[2StrokeFreak]

First off ditch the BR9ES plug for a BR8ES.
If you think its running fat do your plug chops, and jet accordingly.

No one can tell you what jet will work, too many variables.Read your plug (http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html)

use this link to read your plug, do a search on plug chops if you dont know how.

good luck

[707trx250r]

Thanks for the reply. I was wondering why I shouldn't run the br9es plug? And can I run the br8eg plugs, since I have some.

[2StrokeFreak]

BR9ES is a colder plug than the BR8ES. You can run a 9, but with jetting issues they will foul easier and the motor doesn't run as crisp.

Yes you can use a BR8E-whatever. I like the IV (irridium) I get a whole season out of one of them, but they are expensive.

I get them tuned on regular cheap plugs then switch to better plugs later.