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Starting issue
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Posted by: hondardr4life

When I start my R, it will usually fire on the 3rd kick, and instead of just idiling, the RPM's skyrocket, and then gradually fall to an idle over a time period of 10-20 seconds. I have no clue what could cause this?? I'm running a 38mm a/s carb, bored .030 over, full MX port/polish, shaved head, rad valve, fmf pipe, and I'm usuing leaded 110 octane gas in it. What do you gusy think my problem could be. My guess is that I'm rich on the pilot jet.

Posted by: zedicus00

is the slide closing all the way when u let off the throttle

Posted by: hondardr4life

yes it is

Posted by: hondardr4life

Bump, I really need to figure this problem out, I am worried that it will cause my motor to wear out extremely fast.

Posted by: matt250r21

Sounds like you have an air leak somewhere. I would check the reed cage gasket, intake boot (behind the carb) and the crank seal behind the flywheel for wear.

Posted by: hondardr4life

That makes a good bit of sense, I will check for an air leak. But the question is, would the rpms settle back down even with the air leak?? The motor didnt start doing this until I rebuilt the engine, and changed the carb. I have a boyesen Rad valve, and I know that their boots are known for ripping, so I will be sure to check that.

Posted by: TravEX

I've been following this thread to see what is said.

Mine revs up a little when started, and I've accepted that it's normal. Now I wouldn't consider 'skyrocket' to describe how high mine goes, maybe like a 1/4 throttle blip. How high does it rev? Like 1/2 throttle or so?

Do you pump the throttle a little while you're kicking it? It could be some built up gas burning off.

What pilot and air screw setting are ya running? What oil brand and ratio?

Posted by: lee37vernon

leakdown test !!!!

Posted by: hondardr4life

Well, when I say skyrocket, I mean like damn close to WOT. I do not blip the gas or anything while starting. This problem has really been bugging me lately, and I have been thinking a lot. I remembered that when i rebuilt it, I did not put acorn nuts on the head because the moron at the local shop claimed I didnt need them, and some of my stock acorn nuts were ruined. So I just put regular nuts on, because they didnt have acorn nuts at the dealer. When I started the quad, there was coolant leaking out of the tops of the nuts. So, I bought some acorn nuts, and I removed 1 of the regular ones at a time, and then replaced it with an acorn nut until all of them were replaced. After that, I had a little bit of coolant leaking out my head gasket for a while, and IMO, there is still maybe a drip or 2 that leaks out when I ride. My thought is that maybe some air could be getting into the cylinder through the head gasket while it is cold, and then once it gets warm, the gasket seals, and quits letting air in. How does that sound for a theory???

Posted by: hondardr4life

What do you guys think about the head gasket?? Does it sound possible? I just need an opinion or 2, and then i'll order a cometic head gasket.

Posted by: matt250r21

When I had to run CR250 head gaskets I always had to use that copper spray on gasket maker. You can find it at an auto parts store, its kinda cool, gasket in a spray can. Might help your head gasket problems.

Posted by: 86250rrider

i had the same problem after the last rebuild. i would almost bet its the head gasket seeping.i also started using copper-shield then and it hasnt happened since.i now use the trx gasket split with coppershield, no leaks here .

Posted by: dober250R

if you mill the head, you can't run acorn nuts because the nut will bottom out on the head. I run just regular flange nuts. If you use a CR gasket, you need to use the copper spray. And this does not sound like a head gasket issue. This sounds like a carb setting issue. Try playing with your air/fuel screw and idle screw.

Posted by: hondardr4life

I ran regular flange nuts, and coolant leaked out of them........ I'm pretty sure the acorn nuts dont bottom out even though the head is milled. I'm going to try a cometic flex steel gasket. Maybe that will fix my problem....

Posted by: 86 Quad R

i personally use the three piece gasket(taken apart) and use the thinnest. kewl thing is that you can use it over n over again. after removal i clean it up and coat both sides with krylon paint (color of choice) i havent had a leak in 6 years of using the same gasket.

Posted by: Iliketogofast

Air leak, check the base too.