Hello from California ( Wildomar )

Hey guys, Just picked up a street legal 03 last week. Love it, but I am having a problem with surging at speed. Seems to happen only when it is warm. Going to clean the carb this week and check the jetting also.

Uncorked with aftermarket exhaust. Choke doesn't seem to affect it when this problem occurs. I think (hope) its just a dirty carb. I just had the swingarm off for seized adjuster bolts so I'm hoping this is no big deal.

Wish me luck! Will return Monday with updates.

Jesse

Tell use what your have slow speed jet, main jet, needle and clip setting for the needle.

Look here:

http://www.xr650rforum.com/t1068-how-to-properly-jet-your-xr650r

No change with swaping the main and slow jet. I changed the main to 178 and the slow to 68, wanted the 68s but the guy at the motorcycle shop could not find the 68s. I dont have my notes and cant remember what the jetting was before I changed it also I forgot to check what needle I was running but it was in the stock location

I just gave up early in the weekend because I couldn't check the clearance, it seems that everyone is out of feeler gauges. I haven't owned a four stroke in a while and lost my collection of tools in a garage fire a while back.

So, I need to order some new feeler gauges, pull the carb again and check what needle I am running then report back.

Any air or intake leaks?

Nothing as far as I can tell.

Singletrack Gardener wrote:No change with swaping the main and slow jet. I changed the main to 178 and the slow to 68, wanted the 68s but the guy at the motorcycle shop could not find the 68s. I dont have my notes and cant remember what the jetting was before I changed it also I forgot to check what needle I was running but it was in the stock location

I just gave up early in the weekend because I couldn't check the clearance, it seems that everyone is out of feeler gauges. I haven't owned a four stroke in a while and lost my collection of tools in a garage fire a while back.

So, I need to order some new feeler gauges, pull the carb again and check what needle I am running then report back.

What does the spark plug look like?

You could probably get away with a 70 instead of a 68s.

Are you running a unrestricted intake manifold?

Did you try spraying eyther or starting fluid around the carb and intake while the bike is idling?

Is the choke fully open unrestricted in the off position?

Are both the air filter and exhaust unrestricted?

Did you measure float height?

Pull the petcock out of the fuel tank and inspect the fuel filter/screen. This one might be your problem.

Also look here: http://borynack.com/XR650R/xr650r_caruretor.htm

Hmmmm, that link is very interesting. I will try that next week, taking the kids out this weekend. I have been prepping my other bike and my son's so I haven't had time to play with the pig.

Thanks for all the info, you have been very helpful.

Jesse

Well, its been a while but I think I have it working for the most part.

Got a few tips from a friend who is a mechanic and has pitted for a few baja races. He told me to run the intake valves at a tight .005 and the exhaust at .006. The beast sounds and runs great now. But that wasn't the initial problem.

One of the issues was the petcock filter ( thanks Aurora ) I was kicking myself because that is usually the first thing I check. Man was it dirtly in that tank too. Next was float level, its still peeing after adjustment so I may have a bad float or just another speck of sand in the float valve ( I have found several ). Another issue was jetting, trying to get it perfect still. And the final issue was possible damaged slide. Its not damaged that bad but I am still going to replace it.

I have been tearing this thing apart over and over again for the past few weeks. At least I can have the carb out in about one minute now, no joke. I did the valves last night in about five minutes total time with putting the seat back on. So I guess the positive about this whole dilemma is I pretty much know the carb inside out and can work on the bike much faster

I'll try to keep updated with what is happining with the beast and pictures and such.

Thanks, Jesse

Singletrack Gardener wrote:Well, its been a while but I think I have it working for the most part.

Got a few tips from a friend who is a mechanic and has pitted for a few baja races. He told me to run the intake valves at a tight .005 and the exhaust at .006. The beast sounds and runs great now. But that wasn't the initial problem.

One of the issues was the petcock filter ( thanks Aurora ) I was kicking myself because that is usually the first thing I check. Man was it dirtly in that tank too. Next was float level, its still peeing after adjustment so I may have a bad float or just another speck of sand in the float valve ( I have found several ). Another issue was jetting, trying to get it perfect still. And the final issue was possible damaged slide. Its not damaged that bad but I am still going to replace it.

I have been tearing this thing apart over and over again for the past few weeks. At least I can have the carb out in about one minute now, no joke. I did the valves last night in about five minutes total time with putting the seat back on. So I guess the positive about this whole dilemma is I pretty much know the carb inside out and can work on the bike much faster

I'll try to keep updated with what is happining with the beast and pictures and such.

Thanks, Jesse

How does she run?

She runs awsome, put is pissing like a race horse. Like I said I think it may be a stuck float or hopefully just another speck of sand in the float valve. I'll have it figured out by tonight then I'm taking this pig for a nice ride!

Probably just dirt in the needle valve or float stickin........open the bowl drain screw,turn the fuel on and while fuel is flowin out the drain hose rap on the bowl with a screwdriver handle or something, it`ll knock the dirt loose if this is the problem....then tighten the drain screw and see if that helped, if not you gotta pull the carb and tear into it..

Gardener,

the std carb is a bit prone to leaking, when on its side it will do it too.
Set the floatlevel at 17mm, it will cure your problem and will not really affect your settings. Re-adjust the idle if it needs it, that's all.

I'm in Canyon Lake. Howdy neighbor!