Snowmobile Repair: 88 wildcat...flat spot, unnecessary money, leak down test

Question
i got a 88 wildcat 650..38 mikunis...carbs are cleaned/adjusted...(the kid who had this put on psi racing pipes..i dont think its jetted or clutched)....i have to pull sled about 3-4 times..starts on 1 cylinder...slowly i raise to 3000-3500..then..POP..it hits both...flat spot at start..then catches up and pulls hard..then feels like no gas..i can put choke on for a quick up.down.twice..then it goes..has to be high revs tho....check plugs.mag side wet/fouled..pto perfect.....my ? is .reeds or crank seals.....i trust your comment/response..just trying not to spend unnecessary money..thanks, rick...p.s.  pto 136 psi..mag 132 psi

Answer
Hello Rick,

 I just had basically the same problem with my El Tigre, and found that it was an air leak causing the problem. It was the rubber carburetor boots/flanges that were cracked. So, that would be something to check. They don't cost more than 10 dollars a boot. Your Compression sounds real good. Leaking seals in deffinitely a good possibility, but before spending the money to replace them, I would recomend a leak down test, to see if it needs the seals replaced. You could buy a tester, but most shops will check for hardly any money. You can get almost any part, here for your sled: http://www.denniskirk.com/jsp/product_catalog/mmy.jsp;jsessionid=BT5ZW2VL0LCNNLA... . Make sure there are no restrictions in the exhaust or air box. Try carefuly tuning the carbs, too. I hope this helps you. Let me know if I can help you at all, with any questions. Best of luck to you with the sled, hope you get it running good, before all the snow! --Arcticatman