Help - Bike not starting correct......

So I tore my bike down a while ago to do a rebuild on it. Put in a JE hi comp piston, new valve seats, new valves (stock ex, RHC Ti intakes), a PC valve spring kit, port and polish and a hot cams. For jetting I am running a 48 leak, 42 pilot, fuel screw 2 turns out, 168 main, needle on the 3rd clip and its all flowing through a Dr.D exhaust. All of my valves are clearanced perfectly (I have checked about 12 times now), and the cam is lined up the way it should be on TDC, its not a tooth off because thats what I was thinking.......

Now for the problem..... I cant start the bike by kick starting it (whether hot or cold) only by bump starting it. However, once its running it goes like a bat out of he!!. It wont idle unless the choke is on, in which case its idling high. So what do I do? I need to be able to start my bike my kicking it and I need it to be able to idle, without me rapping the throttle.

what fuel you runnning & can you run pump with the je? maybe the spark is having hard time with high compression/check plug---sounds like advanced timing---doublecheck that one tooth---read also of cam gear moving on shaft[pressed fit]--decompressor?

Just curious why you went with a 48 leak jet.I just changed to a 55 and also had problems starting.I had none with stock leak jet.I bet iti is the leak jet.

It wont idle unless the choke is on, in which case its idling high. So what do I do? I need to be able to start my bike my kicking it and I need it to be able to idle, without me rapping the throttle.

Adding choke richens the mixture, so it seems that you're really lean on the slow jet circuit? Is it possible your slow jet is clogged? Have you tried cranking the bike with the pilot screw at 3 - 4 turns out? If that does fix it, you need a larger slow jet.

Thanks for all the tips. I was talking to a bunch of people at the track today and have some stuff to try. I am going to remove the auto-decompression from the cam and see if that fixes it. If not I am going to pull the carb and make sure the idle circuit is clear. If all that fails I will prolly check the cam to make sure it is degreed in properly.

I'd go w/ what skipn8r says and clean the pilot.

Does changing the leak jet size have any affect on starting ability?

Does changing the leak jet size have any affect on starting ability?

Nope. It only comes into play when RPMs are low and you open the throttle.


So I popped the valve cover off the new RHC intakes hadnt moved at all, both valves were still dead on spec (.005) and the exhausts hadnt shifted either. I was able to pull the auto decompression without even having to remove the cam from the head. Buttoned it back up and the damn thing fired up first kick. :naughty:

The bad news is that it still isnt idling, it will idle at a high RPM after I rev it for liek a second then it falls off and dies, almost like a vacuum leak but I checked everything and it is sealed up perfectly. I currently have the fuel screw out 2 turns with a 42 pilot so I am guessing that it is jsut a lean condition. I will try popping in a 45 pilot tomorrow and see if that makes a difference.

Great new on the valves. I would try turning the fuel screw in to lean it out a bit and see if it

cleans up. I assume it's run good before and your temperature and

humidity are higher now, thus making the bike run a little richer.

Did you clean the pilot?

I jsut put the bike together so this is a completely different compared to the wya it was before, I definately dont think im too rich, I think im lean. I had the carb off the bike and the pilot is clean.

Double check your cam chain tension. I have seen these things not want to start if the cam chain is too tight. :naughty:

I have a similar problem except that mine idles fine. I replaced the rings, did some mild head porting, and new DRD exhaust. Stock pilot and leak jets, 170 main, jd (red) needle, clip 5th position. If the bike is warm it will restart first kick, even if dumped over in a crash or stalled. If it has only sat for a few hours it will also start first or second kick. But if it has sat for more than 12 hours, it is PURE HELL. It took me an hour to get it started the other morning. It idles great and runs awesome though. It runs better than stock now, with the DRD exhaust. I can't figure out what's up.

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