So got it all back together idles great but once in awhile it will backfire out the carb and when it first starts up if i hit the throttle it stalls but after a few min of warming up its fine have no problems when riding it just when it starts up any ideas i thought it might have something to do with intake valve not sealing right i replaced al the seals and cleanded up the valves

 

again i said no offense. and gear selection and feathering the clutch with the brake kinda helps. usually where i ride, we use the 4 second rule. we ride old high wall mines and stuff of that nature, where the trails are steep and almost always have a minimum of a 100 foot drop on either side. i have only been riding a clutch drive 230 since December of '09.

and here is a useful tip, always plot a course that will get you around an object, even if its another rider, but safely. i am still recovering from a bruised brain and several fractures because i didnt think ahead and took a jump wrong and turned my 230 into a Christmas tree bulb, then had it land on my head and chest. so always think ahead at least 4 seconds.

 

sound like you gotta really cold natured 230. your intake valve may have somethin to do with it. 230s are notorius for bending intake valves. i would have the valve seats recut and new valves put in, maybe new valve guides as well. but thats just what i did during my rebuild, still waiting for my crank to come back from the shop.

 

Could be your carb. My dad owned mine before I took it over. He always said it was cold hearted. When I first got it it was. I eventually got so that I dont have to even use the choke, I just give it about 1/4 throttle and it starts and stays that way.

It took me a long time to get to know my carb. You can clean it up real well, take all the jets out and clean, clean, clean. I like to take the choke and others out and clean em too. If you turn your pilot screw out 2 turns, and start your quad. you can then fine tune your pilot screw. For me it is usually around a 1/4 of a turn either way. It sometimes takes away the backfire.

The backfiring though, I agree could be the intake valve not sealing properly. I am just glad I live in Michigan where places are hurting for money, and normally we can get things done a little cheaper.