426 hotstart and carb. problem

4 replies to this topic
  • viperman

Posted January 17, 2005 - 04:23 AM


My buddy bought a mint 01 426. Since he got it, the hot start never worked.
We took a look at it, and as posted in the forums, it was frozen in the carb.
from lack of lube.

We tryed to pull the plunger out, but it was solid. We drilled it out carefully
increasing bit sizes until we could get it out, finally we could grab it.

We drilled it out on the bike, slowly, with a shop vac cleaning chips, and
with it disconnected from the intake.

After removal, it started fine, but had a high idle, and would back fire at
heavy throttle. I thought is was running lean because there was no plunger
in there and it was pulling air thru the jet(we didn';t have the replacement
hot start yet). Well, the new Dr. D just came in, we installed it, and the bike will run with the choke out, but after you push it in, it will not idle. The bike also pops on heavy acceleration with
the choke in.

We tryed adjusting the idle, but no go. SImply will only idle with the choke on. Could we have screwed up the carb. drilling it? I'm guessing we scored the plunger bore and now the hotstart is leaking instead of sealing....

Any ideas on this......Thanks.

  • sirthumpalot

Posted January 17, 2005 - 05:34 AM


Start by cleaning the carb out completely. There is no telling what little chips may have gotten in there. Also did it run OK before your hot start surgery, aside from not having a hot start? I don't know if there is any way to clean up the hot start bore, that's a tough one... Fortunately there some people here much more creative than myself, hopefully someone will have the answer for you.

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  • Matt96xr6

Posted January 17, 2005 - 08:19 AM


pull the carb all the way down, remove the slide, jets, Accel pump and clean everything out. Then use compressed air to blow all the passages out. Reassemble and try

Usually if you cannot get the idle screw to work, you have the pilot pluged up or a massive air leak.

  • grayracer513

Posted January 17, 2005 - 09:48 AM


Go to a sporting goods store and buy a brass rifle barrel brush for a 6mm bore. The bore in the carb is short enough that you can work the brush with a pair of pliers, so you don't really need to buy a rod to screw the brush into. Be sure that the hot start plunger will run all the way in to the bottom of the bore, and not stick part way down. That sounds like a possiblity in your case.

The info concerning the pilot jet is correct, too.

If you get it cleared up, here's a tip about the remote hot start kits. None of them seal as well as the stock set up, and you will get water in around the plunger when you wash the bike. Some people recommend removing, cleaning, and lubing the plunger after each wash, and that does keep it from sticking again. What I do is simply start the bike after washing, and as soon as it will run without the choke, I hold the RPM up a little ways and hold the hot start open for 15-20 seconds to draw any water out of the circuit. If I do that, it never sticks. :cry:

  • viperman

Posted January 17, 2005 - 04:59 PM


The bike ran fine other than no hot start initially, which really sucked. He only rode it
once, it stalled and he could not get it started due to the frozen hot start. Then
we figured out the problem, drilled out the frozen hot start, replaced the entire
DR.D deal with a new setup and reinstalled. That's where we are now.

Sidebar.....when we removed the frozen hotstart....I started the bike with no plug
or anything in the bore. The bike started right up but did exactly what its doing with
the new hot start in place. Popping and idling only with the choke out.

Old hotstart completely removed, bore completely open to atmosphere....popping and idling only with choke.
New hotstart installed and .......popping idleing onlywith choke....So my guess would
be an air leak as others have stated....

My buddy, not very mechanically inclined, just wants to take it to the shop.....
I have a need to fix it for my own personal satisfaction.....

You guys rock!

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