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Old 01-20-2002, 10:19 PM   #1
Miktole
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Hi I have a 1997 Vmax 600 twin, it seems to take about 6-8 pulls to start it when it is cold, then when its warm and you restart it after you just turned it off you have to feather the throttle alittle, then it will idle fine, once in a while after riding for awhile shuting it off the restarting about 5 minutes later it will let a back fire out and blow black crap out the exhaust, today it seperated the pipe where it is attached with two springs that go to the Y pipe that goes into the moter, What do I do or check please help.
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Old 12-01-2003, 07:59 PM   #2
tmkrukow
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my brother had this problem with his v-max.
first thing check the plugs to see if it is running lean or rich.
back firing is usally caused from lean mixture,dirty carbs or also could be dirty fuel filter.
hard starting has to do with about the samething.
check float levels, make sure carbs are in sink,check and make sure choke postions are the same.
pilot airscrew is 2 turns out
float height mm 22.3+-2.0mm
idle speed 1600 rpm
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Old 12-02-2003, 06:56 PM   #3
FuzzButt
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I agree.

I have a '97 VMax 600 XTC. It has very similar behavior that clears up after a plug change. I bet the carbs are dirty. I would start there. My machine loves the cold start lever on full when cold starting. 1/2 when starting warm. I have electric start so I can spin it for a few instead of yanking 6 times.

The circuit to check are the pilot air jet. That one is what feeds gas from the float bowl at idle to 1/8 throttle. Being plugged will cause lean condition and backfire.

The TORS could also be malfunctioning or you do not have the proper fuel flow. Cleaning the carbs out should help this.

Now I wish I could tell you how to clean them but I am just learning my self. I am in the process of finding a book on it and then cleaning my other sled's carbs first before I screw with the VMax. I have thought about just taking it to the dealer for cleaning but I would rather not have to part with any money if it is something I can do.

If anyone has hints on how to easily service these TM38 carbs please post ideas.

Chris
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Old 12-20-2003, 11:54 AM   #4
sno_nuts
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Get a manual and it will walk you trough it. After you do it the first time it's alot easier after that and fyi you don't have to separate the carbs to clean the bowl area and the jets, keep them attached to each other and flip them upside down and do one bowl at a time so you don't get the jets mixed up since usually there is different jetting in each carb to help sync the cylenders together to compensate for temperature, exhaust flow, ect. getting the carbs off and back on is the hard part and the most time consuming, cleaning the bowls and jets are gravy once you get the carbs on the work bench
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Old 12-20-2003, 12:47 PM   #5
FuzzButt
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By the way since I posted my reply I have cleaned my TM's. It was a so much easier that I thought. It is something you can do with a few tools.

I have the complete instructions on another post here somewhere. It takes about 2 hours start to finish. I am going to do mine each season. There is no reason a mechanically inclined person can't do this.

Shoot me a PM for more info if you want.

Chris
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