XR650R Jetting question

[Pig_N_CR5hundy]

Bought a 2002 XR650 brand new, back in 02. Had it uncorked, HRC tip, jets, intake, you know the basic uncorking. Ran great.

Put a White Bros E2 on it. This thing backfires to all hell on decel. However, looking at the plug, it is a nice dry chocolate brown color.

Also won't idle very good unless I turn the idle screw, then when it gets hot it revs.

Now, I think the idle issue has to do with needing a good carb cleaning, but other than that, based on my symptoms what do I need? A larger jet to allow more fuel? Just a needle placement issue? I am at seal level and it seems to have these issues all the way up to about 3000 feet.

Thanks in advance for the help:thumbsup:

Chris

[philipstjohn]

what jetting are you running and the needle seat position?

[Pig_N_CR5hundy]

I'd have to look, but whatever the "standard" is for uncorking the pig is what it is at.

Looking at the White Bros website, the jetting specs for the E2 on the

XR650R is "stock", which means the uncorked jetting specs do not work for the E2, as the uncorked specs are not stock.

[arctic954]

This is a link to a kick-butt jetting guide for modding the XR650R....

http://www.xr650r.us/jetting/

Ode to the 'Pig Pen'

[Pig_N_CR5hundy]

right.........but jetting with an E2 pipe is not the same as with a stock pipe w/HRC tip.

[arctic954]

..... or....

you can say....screw it, drop a little cash and pick up the Edelbrock.

Every mod I've done now --- literally takes me a couple of runs and shes ready to go. (it has an externally adjustable needle height....)

This so far has saved me HOURS of tuning. Especially after I just installed a Hot Cams Stage 1.....

Sure ---- you probably can get more power out of a few other carbs....but for tuning quick --- and something that doesn't involve jets....its sweet. (I also noticed a huge increase in power via. the pumper --- no more hesitation & 3rd gear wheelies....)

[jws]

I'd have to look, but whatever the "standard" is for uncorking the pig is what it is at.

Looking at the White Bros website, the jetting specs for the E2 on the

XR650R is "stock", which means the uncorked jetting specs do not work for the E2, as the uncorked specs are not stock.

The only thing different is your E2 - You are still uncorked with the airbox plugs out, bigger intake, HRC needle. If your jetting is the standard Uncorked jetting it would be 175 main and a 65s pilot with the clip in the middle on the HRC needle. A lot of us have put in the 68s pilot. I would think that should be fine. Might try a 178main to richen it up a little

When was the last time you checked your valves?? when mine starts running like shit I adjust the valves ( my intake are always tight after 300-500 miles) Then I clean the piss out of the carb, put a new plug in and fresh gas:ride:

I really think your jetting should be pretty close - a little popping is normal.

But the QS is the carb to have for these Pigs - if your looking to spend some money:thumbsup:

Jeff:cheers:

[Pig_N_CR5hundy]

The only thing different is your E2 - You are still uncorked with the airbox plugs out, bigger intake, HRC needle. If your jetting is the standard Uncorked jetting it would be 175 main and a 65s pilot with the clip in the middle on the HRC needle. A lot of us have put in the 68s pilot. I would think that should be fine. Might try a 178main to richen it up a little

When was the last time you checked your valves?? when mine starts running like shit I adjust the valves ( my intake are always tight after 300-500 miles) Then I clean the piss out of the carb, put a new plug in and fresh gas:ride:

I really think your jetting should be pretty close - a little popping is normal.

But the QS is the carb to have for these Pigs - if your looking to spend some money:thumbsup:

Jeff:cheers:

Hey Jeff!

I might do a carb after the new year, just trying to get it right for LA B2V. I did my valves a few weeks ago, no problems there. It has ran like this for quite awhile, ever since the E2 was installed. Tons of power at speed, just pops like crazy and won't idle at all unless it has been running for an hour or so. No biggie, I can run it like this but if I can get my hands on a stock pipe and an HRC tip before Turkey day I will go that route. BTW, heading out to Ocotillo for the New Year, you headed anywhere?

Chris

[jws]

do you need just the can??? were off to spangler in 3 days

[larry650]

I would verify what pilot jet was put in your bike. Backfire on deccelaration issues usually occurs with the throttle completely closed [eliminates the main-needle circuit]. Errattic idle also suggests a lean pilot circuit. You can adjust the fuel screw [part of the pilot circuit] from the right side of the bike.

[Pig_N_CR5hundy]

do you need just the can??? were off to spangler in 3 days

Yeh, just the can, I will buy the HRC tip. Your old can lying around?

Chris

[jws]

Yeh, just the can, I will buy the HRC tip. Your old can lying around?

Chris

PM sent:ride:

[pgiinc]

you still have to take the seat and tank off to touch the adjuster. Now if they would extend it/hang it over under the gas tank like the idle screw it would be nice