2002 Xr650r

[rschwing]

Hi all,

I know this topic has been discussed before, but because I have seen a few variations
concerning this, I feel the need to address it some more. I just bought a 2002 XR650R
and am in the process of making the required modifications to uncork it. I have removed
the two air box restrictions and am looking to next replace the Intake Manifold and re-jet
the carburetor, or should I first replace the stock muffler tip before doing any carburetor
work. I live in the Denver, Co. area and am looking to ride this bike mostly in the
mountains between the elevations of 6,000’-9,000’ range, with 7,500’ feet being the
optimal elevation. Jetting for this elevation, I think would provide for good riding 1,000’-2,000’
above and below this elevation. The problem is I have seen quite a few variations of Main,
Pilot and Needle Jets recommendations. Anywhere from 150-175 Main Jets; retaining the
stock 65S Pilot Jet or moving to a 68S Pilot Jet; retaining the stock Needle Jet, but changing
the clip setting or moving to the B53E Needle. Could someone please try to make this a
bit clearly and easier for me.

Thank you

Ron

 

[Buckholz]

I live at 7,000'. Had a 2001 XR650R for a year.

For my elevation, run stock needle in 3rd clip. Run a 68S pilot. Run 165 main. When riding at 10,000' plus I went to a 158 or 160. If riding below 3000' you need to move the clip to 4th. I ran 170 mains at 3500, and 175 mains down at sea level. If racing down low, a 70s pilot will help boil over.

Above jetting was with XR fully uncorked. Oh ya, check your right footpeg bolts regularly, and run a 1.6 KX500 optional rad cap.

 

[rschwing]

Thanks Buckholz. This is very close to what I was thinking, but I was thinking of using a 168 Main. Any reason why you decided on a 165?

 

[Buckholz]

I'm AR on my two strokes, but my four strokes I only jump jet sizes in increments of 5. Can't hardly tell the difference, and with humidity and temp changes, not sure much difference in 168 v 165. 168 would be safer.....


You boiling over any?

 

[rschwing]

I have been seeing alot of 165 and 168 responses. Why would a 168 be safer? I wanted to wait and uncork the bike before I hit the trails, so I
haven't had the chance to see if the bike would boil over. I have heard
that some of the bikes do. but not all. I was thinking of using the Evans coolant and leaving the radiator cap stock and leavin in the thermastat. If I had problems after using the Evans coolant, then either go to a 1.6 radiator cap of remove the thermastat. What is your experience?

 

[Buckholz]

Richer is always safer.

Don't even ride the bike without uncork. The 125 main that comes with it is too lean, even with corking.

The negative with 100% propylene glycol (Evans) is that it won't boil when you get too hot. The phase change that takes place during boil over absorbs alot of heat.

If you don't ride first/second gear tight trails at a fast pace, you probably won't boil over.

165 vs 168 still can't tell much difference, IMHO, no matter what the "experts" say.

 

[Buckholz]

Oh ya, join XR650R@yahoogroups.com They'll give you much better info on the Big Red Pig.

 

[rschwing]

I did join that group. Your right, alot of good info. What does IMHO mean?

 

[rschwing]

Oh, when I replace the Intake Manifold, do I need some type sealant between either side of it, before bolting it in place?

 

[Buckholz]

No sealant required.

In My Humble Opinion.........

 

[rschwing]

Thanks for your help Buckholz.