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2 out of 3!!

1437 Views 27 Replies 9 Participants Last post by  Bobinwi
Having difficulty getting my 90 650 triple to run smoothly. Cleaned all the carbs, syncronized etc, new plugs.

There is spark in all three cylinders, however the cylinder on the clutch side is not running (cold exhaust, others hot)

Any suggestions?

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sure all your sliders are moving? check commpression? thourouglly cleaned all jetS?
Just to be sure and as a process of elimination. switch the clutch side plug and wire with one that works. if the problem moves check plug and wire. If the problem stays you know the plug and wire and coil and primary wiring is ok. then you check compression and fuel problems.
Let us not forget about compression....this is a must to have a good running engine. Air, Fuel, Spark, and compression....those are the basics.... let us not forget the basics.

Oops sorry Sled Dog, didnt see that in your post.

Polaris is my way out - Other people just use a door.

Edited by - TriumphoverU on 03 Mar 2002 20:56:36
Let us not forget to read the end of the post above. LOL
Thanks for the quick reply, I will try this afternoon and advise.
<BLOCKQUOTE id=quote><font size=1 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote> let us not forget to read the end of the post [/quote]

let us not forget that a smooth running engine makes a happy rider....hehe
sorry hotrod, i couldnt resist that one

1993 xlt sp 580
xtra 10 suspension
Sorry for the delay in getting back.

Switched the plug wires around and the clutch side exhaust is still cold.

Any suggestions??
I had a similar problem with my triple, but the cylinder I was having a problem with was the one furthest away from the clutch. I took it to the shop and they said it was a problem with the choke cable - all cylinders were running too rich and one just was just way to rich. They put in a new cable, adjusted, and all seemed great! Now I am having the same problem again? bummer...

1997 ZRT800
now you have to do a compression test to see if your seal or piston/rings are bad. If you dont have one you can do a preliminary test by holding your thumb over the hole. compare with the middle.
Compression was 95 psi in all three cylinders.

Had a problem with this carb when I purchased the sled. It was sitting for 2 years and the plunger in the carb was stuck. I soaked the whole carb in cleaner to release it.

Did I damage something in the cleaner?
Ok this new info puts a whole new slant on things. You have spark and you compression. now you must have fuel and air. when you run the sled and that exhaust feels cold hows the plug look after.... wet ? dry? let me know.
HotRod thanks for the reply.

After running the plug is wet and oily, so it appears its getting gas.

How's the snow up in Muskoka?
If its wet and oily. Then i guess you will have to remove the Carb and go over it again. If you dont know what to look for let us know. I dont want to type it all again unless i have to (one finger typer) .I havent been up to Muskoka lately. You can check all the trails in Ontario by going to OFSC site and getting the trails pull down then Trails by region.
I originally took it off and cleaned it with a tooth brush and blew it clean with a compressor. However I did not take any thing appart besides opening the bottom where the float is.

Any suggestions? Point form would be great, or any websites.
Yeah, you definately want to pull the individual jets out and really make sure that the small holes in them are free and clear of any small pieces of debris.

1997 XLT SP 600
"Engage the Mechanism"
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95 lbs of compression dosent seem high enough. even if all 3 are 95 lbs., that tells me that the motor is worn out. that machine should have at least 125-130 lbs. per cylinder.If all jets are cleaned, carbs in sync, seals in ok condition, good spark ect. then it needs a bore job. just my .02 cents worth. later ROTALARIS
Ok hear goes. Because it is rich at idle we will look at that circuit first. check slide clearance with an appropriate size drill bit to make sure that slide isnt higher than the others.make sure the plunger rubber on the choke is good enough to seal the choke jet. Make sure the plunger is not binding. The hole in the bottom of the choke bore must be sealed to shut off that choke. Check the number of turns the idle air screw is out and make sure it is the same as the others. Remove carb and float bowl. flip carb uside down and check that the arms of the float lever are parrallel to the body of the carb. check the floats to make sure they arent fuel logged. remove the pin holding the float lever and remove the needle and seat. check condition. Remove the Idle air srew and check its condition. Down the bottom of a narrow tube is the pilot jet, remove it and check its size. I think it will be a 50. With me so far ? thats the idle circuit. Once you remove the main jet and needle jet you can clean and blow out with Compressed air. Pay special attension to the little idle air passages. Good luck. some one posted a site for mikuni carbs a while back but I cant find it . maybe they will post again.

Edited by - hotrod on March 08 2002 5:13:44 PM
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True rotalaris but every one tests compression differently and their testers arnt always accurate. Weve had a discusion on here before about how to test compression so I dont want to get into it again. the Problem is just one cylinder so maybe the others would be acting up too if it was too worn out.
yeah to me the compression does seem low but if that were the case all the cylinders would be acting up. my suggestion would be to swap the problem side carb to another cylinder and see if that problem moves with the carb if so you found your problem
let me know what happens if you do this


My wife said its me or my sleds... Im sure gonna miss her
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