I've been asking this a while myself, can never seem to get an answer, but I've used JB weld in the transfer ports which would get considerably hotter than the case due to the direct exposure to exhaust gases. so whatever JB welds melting point is, it's less than that. I have stuffed my case though, but using Permetex copper gasket maker probably not advisable, but hey, it works for me. Only reason I used it is because I ran out of JB. Aluminum's failing point in an engine is around 450*F if I remember correctly (I remember seeing a chart but I cant remember what site), not including other factors (proper torquing, good mix, proper timing, etc.).thanks tom well ive been looking thru the old posts and seen quite a bit and yes sir i completly understand about proper preparation...just curious about what the current thought on the subject is...i understand you are against jb weld (from older posts ive seen)...one question i have is what is the approx operating temp of the crankcase under load.. would a laser temp pointer give a accurate enough reading?
Reason I stuffed my crank was to get primary compression back from drilling the crank. I decided to run it without stuffing and melted the JB weld and blew out my crank seals. You NEED the pressure to overcome the exhaust gases. However just as maniac said, spare parts. I happened to have a whole spare motor that wouldnt run for spare parts, so I only modify what I know I can replace should something go wrong. Getting arrow reeds? probably should stuff the case, RSE reeds arent too bad for compression loss so they're nearly a bolt-on (aside from reed porting). With the extra transfer from reed porting, you'll want the extra case pressure to prevent exhaust gases from blowing into the case and melting your reeds, seals, or just all-out grenading (because before the reed port, your pressure was concentrated in two transfers. With the extra port, that same pressure is now divided by 3 transfers, lowering transfer pressure). The motor, stock, runs fine. Too much compression and you'll blow all your air/fuel mix straight out the exhaust and waste alot of power and gas, too little, and as stated above, bad things happen. So unless you've modified how your motor is fed it's air/fuel mix, modified parts that dropped your pressure, or increased cylinder compression via a new or modified head, you dont need to stuff it, it's harder on the bearings and seals if you do, so do it out of need, not out of boredom.thanks for the words of encouragement Maniac...i will take heed your advisement...however i am bored and do have a multitude of spare junk and maybe even a lil skill as well...thanks
I agree with you on most everything maniac - but I totally disagree with you here. I have a 66cc china with a 35$ puch head, ported cylinder, massive moped pipe (used $25), 21mm dellorto carb ($35) and hours and hours of tuning and I can totally outrun a friend of mine who has a moroni (not even a clone!) His tops out at like 35-40mph. I know this may be a rare situation but what im trying to say is that it doesnt take a whole lot of money (sub $150) and a little knowledge / reading of graham bell's two stroke performance tuning handbook to get a 66cc china really screamingUnless you have serious cash and like spending it in big batches, a full race china girl is probably not for you. The cost and level of modification required to get the HT even close to the Morini's power make building the HT a waste of time.
The only way you will ever get the ht to run with the Morini/KTM would be to build one from scratch from all billet.
And even then it would need to be totally redesigned with ignition, porting and balancing upgrades.
Where did you find a dellorto that cheap? I'm looking for a 19-21mm as well and cheapest I can find is $75I agree with you on most everything maniac - but I totally disagree with you here. I have a 66cc china with a 35$ puch head, ported cylinder, massive moped pipe (used $25), 21mm dellorto carb ($35) and hours and hours of tuning and I can totally outrun a friend of mine who has a moroni (not even a clone!) His tops out at like 35-40mph. I know this may be a rare situation but what im trying to say is that it doesnt take a whole lot of money (sub $150) and a little knowledge / reading of graham bell's two stroke performance tuning handbook to get a 66cc china really screaming
http://www.aliexpress.com/item/new-...ck-21mm-Racing-Carburetor-Carb/692935087.htmlWhere did you find a dellorto that cheap? I'm looking for a 19-21mm as well and cheapest I can find is $75
By all means, if you want to play with ht's, have at it!thanks for the words of encouragement Maniac...i will take heed your advisement...however i am bored and do have a multitude of spare junk and maybe even a lil skill as well...thanks