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Discussion Starter #1
Hello,

I am wondering where I can find info / specs on ajusting my carbs so they are in sync, throttle and choke cables set right, etc??. I have the carbs apart to clean right now and was wondering the gasket for the lower bowl... Do I need to replace them or can I re-use??. I just bought a clymer manual but it will not be here for a couple weeks and I would like to get it back together and running by then. This is for a 88 Wildcat 650.

Thanks,
 

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i would suggest letting your local mechanic dial in the carbs,you have to use mercury stix to make sure both flow the same,this tool is expensive.as for the gaskets if they didn't tear they should work fine.
 

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Syncing the carbs can be done using a drill bit. I want to say use a 3/16 drill bit ( you should be able to find out what size gap needs to be under the slide and use the corresponding drill bit). Put a drill bit under each slide and then slowly push the throttle. You will see which bit drops first, use the nut on top of the slide to adjust the slides until the bits drop at the same time. Then pull the throttle full open and check to make sure they open evenly up at the top.
 

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Discussion Starter #4
Thanks for the replys, I have cleaned the carbs but they still seem to have a greenish discoloration on the lower bowl metal. I guess that will be ok since I scrubed (with carb cleaner)for a while and it does not come off. There was alot of crap built up in there though that all came clean. I think I have this all under control to set the carbs but I sill need to know the proper setting for the Air screw? and the size gap under the slide?. Also what should this machine idle at?.

Thanks again,
 

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It should idle about 1800 RPM but every machine is different. That green crap is varnish, make sure the main and pilot jets are clean. Boiling the carb may help remove that stuff. The air screw should be about 1 1/4 to 1 1/2 turns out from lightly bottomed. The gap under the slide will depend on the Idle speed. As long as they are the same, you'll be OK. If you want perfection, you'll need a carb sync that measures the vacuum at the carbs. But it is not really needed.
 

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Guys you really dont need the mercury sticks to sync the carbs, you can make your own setup that will be just as accurate if not more accurate than the mercury sticks. I got the idea for mine from another website, cant remember what one though. If i get a second when i go back to my parents place i will snap a picture of the "gauge" i made so you can get a good idea of how it works. All that is required is some sort of a test port after the carb slide to hook it up to (primer line ports work well) Then its just a simple step to sync the carbs correctly.
 

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Many carbs have nipples on them already. Did you use gauges on yours Triumph? The best one I saw was a small digital hand held about the size of a calculator.
 

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See if this helps:

http://www.off-road.com/snowmobile/info/howto/carbsync/carbsync.html

I haven't tried it yet but the information in this article seem good.
 

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Thanks XLTSPYEAH, thats exactly the gauge i made. It works beautifully. And as long as you built it correctly and use colored water in the tube, it will be more accurate than the mercury sticks. I suggest using an old broom stick and wrapping the tubing around the rounded end of the stick, and then attaching a chunk of tape measure on the broomstick between the tubing. Basically just get the water level to be the same height while the sled is idling to make sure the idle screws are set identicle, then have an assistant hold the sled just off of idle and again check the water level. If one side is higher than the other, used the cable adjusters on the top of each carb to make the water level even. Once ya get the water level set at idle and off idle, you are done, enjoy your new found throttle response.
 

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I think the article in the link I posted tells you, I seem to remember something about comparison between the 3 in different combinations.
 

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Vacuum at fitting of carburetor is not as much as you would think, and this makes a regular vacuum guage to inaccurate to be used for carb syncing. Only other option besides water, or mercury guages for really fine tuning is the Uni-Sync tool that is sold by many performance shops, but it is about $45US. The drill trick will get you as close as most sleds need
 

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I'm going to make one, it sounds cool, what do they mean by cable adjuster, the one on the top of the carb that adjusts the slides, and where would the hook up be on my ZRT.
 

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I use the same method as Darkstar, but I have only done it on twins. I also use a 3/16 drill bit. Never had a problem.
 

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On my XLT (using the drill bit method) we did the first two carbs and then synced the third carb with the second.
 

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That drill bit method sames to make alot of sense and alot more easier. Good idea
 

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I had used the drill bit method in the past but just yesterday I picked up some tubing to make the one with the antifreeze in it. It seemed to me to be far simpler and you don't even have to pull the airbox. Just warm up the sled, pop the primers or unplug the fittings on choke sleds, hook up the tubes, set idle on 1 and 2, move from 1 to 3, set idle,then move from 2 to 1 and verify against 3, then set rpm at 3000 and set cable adjusters in the same fashion to correct cable slack. What could be simpler.

The broom idea seems even slicker. Thanks,
 
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