marcboy62 Posted February 27, 2011 Report Posted February 27, 2011 Hi, I'm going to put my +4 mill stroker +5 mill long rod crank on my motor and i was wondering if it would work if I just buy a spacer plate to make the head goes higher. Cuz i saw a lot of other topics and people says that we need to change pistons because the rod will push them too high. So, do I need to buy another set of pistons? Quote
jbooker82 Posted February 27, 2011 Report Posted February 27, 2011 Yes you need to buy a nother set of pistons. If you run a 7mm thick spacer plate between the head and cylinders the piston will pop out far enough that the rings will come out of the bore. Long Rod crank requires 795 series pistons. Weather it is a long rod stock stroke or a 4 mill long rod crank you need 795 series pistons. With the 4mill stroker crank you need both the 795 series piston and a cut cylinder head. Quote
marcboy62 Posted February 27, 2011 Author Report Posted February 27, 2011 ok, so what is the role of the long rod if there is a spacer plate that make the head higher? because its like the same thing but the height is to another place.. and how much a 795 piston kit cost?? with a stroker, can I continue to beat my banshee like if there was a stock crank? Quote
gotta_goatsfast Posted February 27, 2011 Report Posted February 27, 2011 You can pick up a 58mm stroke crank with a 110mm rod and use a 513 style piston. As far as I know there is no such thing as a spacer for your head. Not trying to be a dick here!... but why do you want to run a stroker crank anyway? Do you plan on having it ported to the new stroke? You absolutly should run a quality piston. When you increase the stroke you effectively increase the piston speed. A stock cast piston would be begging for mercy. Building a banshee dollar per dollar is way cheaper than building a 4 stroke to make the same numbers... but it still requires money. Don't be cheap about it or you will set yourself up for disappointment or disaster (stock pistons, spacer plates...) Post up any and all engine mods you have right now. Have your stock crank trued/welded. Have your jugs ported by a sponsor here on BHQ, and pick up a top end rebuild kit and you will run circles around a stock port 4mil. Quote
marcboy62 Posted February 27, 2011 Author Report Posted February 27, 2011 Not trying to be a dick here! loll ive already buy my 4mill stroker crank with 5mm long rod, i will buy 2 new pistons kit and im gonna buy a coolhead with stroker domes, but for now i dont have the buget for extra for it and a porting so i need a spacer plate. Quote
bansheesandrider Posted February 27, 2011 Report Posted February 27, 2011 loll ive already buy my 4mill stroker crank with 5mm long rod, i will buy 2 new pistons kit and im gonna buy a coolhead with stroker domes, but for now i dont have the buget for extra for it and a porting so i need a spacer plate. If you buy 795 series pistons and a coolhead with stroker domes, YOU DON'T NEED A SPACER PLATE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Quote
marcboy62 Posted February 27, 2011 Author Report Posted February 27, 2011 If you buy 795 series pistons and a coolhead with stroker domes, YOU DON'T NEED A SPACER PLATE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! DONT HAVE A COOLHEAADDDDDD and it worth twice off the price of a SPACEER PLATTTEEEEEEEE Quote
bansheesandrider Posted February 27, 2011 Report Posted February 27, 2011 DONT HAVE A COOLHEAADDDDDD and it worth twice off the price of a SPACEER PLATTTEEEEEEEE Your post above mine said you were going to buy one!!!!!!!!!!!!!!!!!!! Quote
marcboy62 Posted February 27, 2011 Author Report Posted February 27, 2011 Your post above mine said you were going to buy one!!!!!!!!!!!!!!!!!!! the day when i will have enough money to replace my SPACER PLATE loool by a coolhead Quote
gotta_goatsfast Posted February 28, 2011 Report Posted February 28, 2011 Why waste your time for a marginal performance increase? Save your money until you can fund to do it the right way. Look, you've already got the crank. You still need pistons and a bore/hone of your cylinders. Might as well wait to do it all until you can come up with another $300 or so for port work, too. Spacer plates between the case and jugs are prone to leaking. In a 4 stroke you get an oil drip. In a 2 stroke you get a fatal air leak that will ruin your riding season if you can't afford to rebuild it again. By the way, how much is a spacer plate? I bet you can find a used cool head on here for a similar price as it would cost you for the plate, two gaskets, and longer studs. All you'd need to do is pick up some 4 mill domes. Option 2:You sell the 4mil crank and that will fund your port work. You can mill the stock head for cheap if you desire more compression. You're still going to have to buy pistons and pay for a bore/hone. And yes, you really should have that crank welded.... but you won't need a spacer plate so the money you would have spent on that will cover the crank true/weld. There will be a LOT more power on tap with this vs. a stroked stock port banshee. Quote
Larry's Shee Posted February 28, 2011 Report Posted February 28, 2011 My son's shee has a 2mm thick solid copper head gasket, bought it that way. Don't know who made it, or if it's still available. Would be same as having stroker domes or stock head cut for stroker. Though some argue it creates another place for a leak, the advantage is that port timing will be near normal. With stroker domes timing will be delayed some what. If you need a crank i would get a 4mil , set it up either way, then get porting down the road. JMHO, your results may vary. Quote
marcboy62 Posted February 28, 2011 Author Report Posted February 28, 2011 so, can i buy any brand of coolhead or there is one better than the others, and what size are the domes i need cuz ive seen 21-22-23-24mm, and example : can i buy a coolhead with 22mm domes and change it to a 24mm domes?? thank you guys for your answer its very appreciated Quote
sprinklerman Posted February 28, 2011 Report Posted February 28, 2011 Just have your stock head re-cut for the stroke........cheaper than a new head. Quote
marcboy62 Posted February 28, 2011 Author Report Posted February 28, 2011 hey guys maybe you dont care, but ive just found a prodesign cool head with the domes that fits with the stroker crank and two 795 pistons that just need a set of rings. i will make the cylinders and pistons ported to .75mm and after maybe it will worrk looll Quote
SlowMoe Posted February 28, 2011 Report Posted February 28, 2011 (edited) Just a few options assuming your head is stock and has not been milled IF you run the stock base gaskets with the stroker crank and a cool head you will pick up a few hp over the same stock stroke bike. Mostly in the bottom end/midrange. Or you could run a .080" HEAD gasket with the same results. IF you run a .100" BASE gasket, which is .080" over stock, you will not need any mods to your head, compression would be somewhat similar to stock and you would be good to go. Your port timing would be more radical and you would gain a good bit in the upper mid to top end. OR you can go with a .080" base gasket, stock head gasket and gain some port timing AND some compression and to ME this would be my option if I wanted to increase the performance all around. Actually to be quite frank it appears to me that you don't plan on doing any more mods after the crank and cool head. IMO the gains you will get with that setup and no porting will be marginal and you may be dissapointed. If this is the case and you can somehow get your money back for the crank do that and spend the money on a good port job and get your stock head milled and rechambered by Mull Engineering. The ported engine WILL RUN CIRCLES around the 4mill setup with no porting I guarantee it. Just my opinion Edited February 28, 2011 by SlowMoe Quote
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