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Discussion Starter · #1 ·
Purchased an 08 Gtx with 2200 miles from Utah. I ride in Northern Wisconsin so I re-jetted the carbs and raised the clip. Put on about 400 miles and noticed an engine noise. Pulled it apart and I melted the Mag side piston skirt. Dome was ok and no aluminum on plug. Lower ring was cracked but I assume it was from meltdown. Also noticed needle bearings laying in the belly pan(old crusty needles) which tells me this thing was apart before. Any ideas or advice before I start the rebuild? I don't want to be doing this every year.
 

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Who suggested you rejet? Do you know where this sled was ridden in Utah? If it was ridden in the mountains it would have been rejeted leaner. But then you bring the sled back to Wisc. and you raised the clip again....you should have dropped the clip and put a larger number jet in it. You were running way to lean and burnt it up. Call Sledhead Racing in Oak Grove (north of Minneapolis) talk to Big John about your rebuild. He is one of the sponsors here.If you remember what jets were in there and what you put in it ,that would help us .............good luck
 

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Discussion Starter · #3 ·
Who suggested you rejet? Do you know where this sled was ridden in Utah? If it was ridden in the mountains it would have been rejeted leaner. But then you bring the sled back to Wisc. and you raised the clip again....you should have dropped the clip and put a larger number jet in it. You were running way to lean and burnt it up. Call Sledhead Racing in Oak Grove (north of Minneapolis) talk to Big John about your rebuild. He is one of the sponsors here.If you remember what jets were in there and what you put in it ,that would help us .............good luck
Jets are now a 260 and I dropped the clip, not raised, sorry. And yes, it was ridden in the mountains in Utah.
 

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Jets are now a 260 and I dropped the clip, not raised, sorry. And yes, it was ridden in the mountains in Utah.
The company I work for upped all the jets above stock as we lost 4-5 motors in about a week after they started putting ethanol in the gas. Have not had a problem since. Not sure what size you would need since we run at 6,000 feet and up. But I would definitely run a bigger jet than specs.

nice thing is, once you get it dialed in you should get upwards of 10,00 miles. Our record is 12+. Very reliable motors.
 

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Discussion Starter · #6 ·
check your carb boots....very common cause of failure. jetting was not the problem here. have also had a poorly reinstalled fan belt cost me a motor running spring/hot conditions.
New boots were installed at the time of carb rebuild.
 

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Discussion Starter · #7 ·
New boots were installed at the time of carb rebuild.
Looking for a 550 fan engine guru. I'm going to need some cylinder work done. Can anyone provide a doo talk member or vendor?
 

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New boots were installed at the time of carb rebuild.
LRD does all his own work, great stuff... also you might consider having AAEN do your port work; i have been running AAEN ported cyls. and pipes on my race sled(550x) for 3 years now, very quality stuff. only down side is POOR mileage and some low end losses (just needs more clutch tuning)
also i did a grocery list of mods for 550f a while back:550 mod topic:
 

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Discussion Starter · #11 ·
LRD does all his own work, great stuff... also you might consider having AAEN do your port work; i have been running AAEN ported cyls. and pipes on my race sled(550x) for 3 years now, very quality stuff. only down side is POOR mileage and some low end losses (just needs more clutch tuning)
also i did a grocery list of mods for 550f a while back:550 mod topic:
Thanks for the suggestions. I decided to go with "Big John" at Sleadhead racing. The best part is... he actually answers the phone!
 

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Thanks for the suggestions. I decided to go with "Big John" at Sleadhead racing. The best part is... he actually answers the phone!
Can't go wrong with BJ's work. He'll hook you up nicely.
 
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