Removal of Hot Start

6 replies to this topic
  • rlmeskimen

Posted April 03, 2004 - 08:30 PM



I am installing a WR motor in a TZ250 (roadracing) chassis and had a question about the hot start plunger and hoses. I will be starting it on rollers so I feel I do not need the hot start. To be honest with you it's in the way and I can't get to it anyway and I want to remove it. I will will plug off the pipe that exits the venturi but do I need to plug off the jet on the other side of the circuit or just leave it exposed? Thanks.

  • Matt96xr6

Posted April 04, 2004 - 04:38 AM


what year motor did you get? Only the 03+ have handlebar mounted hot starts.

If you got a 426 carb, they came stock with just a plunger. You could get the factory setup installed back on there -- someone installed an aftermarket unit.

400s have the remote hotstarts mounted back towards the rear tube on the frame.

What year motor was this?

  • rlmeskimen

Posted April 04, 2004 - 05:02 AM


Hey Matt, Thanks for the response. This is actually a 99 WR400 motor. Sorry I guess my terminology is off. The air valve that is used when the motor is hot. It's a plunger that looks kinda like the choke on the side of the carb that has two hoses exiting. One goes to the venturi on the inlet side of the carb. The other hose slide over a jet of some nature. Just wondering if I need to plug off the jet or leave it open. Thanks.

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  • lightestYZF

Posted April 06, 2004 - 05:59 AM


On the 98& 99 motors the intake maniford that is part of the head has a fitting that allows air into the head - hot start is a lean out mixture process. The hot start lever in not integrated into the carb but is an external "switch" thats opens the passage of air from airbox to intake.

You have a couple of options

You could use a Ty Davis hot start. It just uses a long plastic tube to extend the hot start to a handlebar switch they provide.

You could also just plug the intake manifold - but then no hot start and that could make starting tough in certain situations.

You could also just extend the hose and mount the existing hot start swith anywhere convenient. Since it's a road racer you don't really need to worry about filtered air for the short time a hot start is used.

Hope this helps

  • rlmeskimen

Posted April 06, 2004 - 01:21 PM


I understand what to do on the manifold side (plug it off) but the air valve circuit on the carb is my question. I am not not concerned about the hard starting. I have rollers to start it (no pushing or kickstarting) but when you remove the air valve on the carb you are left with an exposed jet and an exposed nipple back to the inlet side of the carb. I would assume you could just plug off the nipple but not sure what to do with that air jet.

  • lightestYZF

Posted April 06, 2004 - 02:48 PM


ok I may be confused since you have a WR. On my YZ the hot start was totally separate from the carb. Just had a hose from intake to hotstart to airbox. Looking at the WR parts diagram for the intake it does seem different for the WR. Perhaps someone on the WR forum can help.

  • rlmeskimen

Posted April 06, 2004 - 03:52 PM


I appreciate it my friend. I didn't know they were different. I posted the same on both areas.

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