paisaroni_mario Posted April 12, 2013 Report Share Posted April 12, 2013 Hey guys, im wondering if I can install a +4mm hot rod crank but still keep my stock bore which is 62mm if im not correct my apologies.. I do understand that the biggest I can go is 66mm bore with a 4mm crank but for now if I do decide to put the +4 can I keep the stock bore? & if you guys have any suggestions to go along with the +4mm crank shoot em. Would really appreciate it.. Oh and I got some black and white uncut plastics in very good condition. Someone down to trade for some drag cut all white ones? Quote Link to comment Share on other sites More sharing options...
Surfrjag Posted April 12, 2013 Report Share Posted April 12, 2013 Yeah you can keep the 64mm (stock bore) your going to need the head cut or coolhead domes cut for the extra stroke unless your going to use the spacer plate. Porting is highly recomended!! Quote Link to comment Share on other sites More sharing options...
Larry's Shee Posted April 12, 2013 Report Share Posted April 12, 2013 If you go long rod you need different pistons. Quote Link to comment Share on other sites More sharing options...
paisaroni_mario Posted April 12, 2013 Author Report Share Posted April 12, 2013 Surfrjaq Yeah bro I bought my banshee with a cut head already so it has that extra stroke.. So since I have a cut head I can pretty much go ahead and install the 4mm crank with the 64mm bore?Larry's Shee, all I thought about changing was the crank for now.. Are you saying I need to change the pistons since im going to change the crank? Quote Link to comment Share on other sites More sharing options...
Surfrjag Posted April 12, 2013 Report Share Posted April 12, 2013 Cut head for a 4mil or for a stock stroke. 2 different cuts. Yes if its a long rod crank it needs stroker pistons Quote Link to comment Share on other sites More sharing options...
Zillaguy Posted April 12, 2013 Report Share Posted April 12, 2013 The combustion chambers in the head need to be cut 2mm deeper so the piston can recieve into them... If you go long rod 4mil you need Wiseco 795 series stroker pistons, so the piston skirts clear the crankshaft at BDC ( bottom dead center). DO NOT USE A SPACER PLATE!!! Have a reputable builder port your cyls. for the stroker. This is not a slap it together and run kind of thing.... You need a coolhead with stroker cut domes, a crankshaft, Wiseco 795 pistons (if you go long-rod), porting for the stroker, all new gaskets and seals, then there are the supporting mods, adjustable timing plate, shifting mods (modded shift-shaft, modded shift star, bearing upgrade for the detent arm), cut trans, Pingle high-flow petcock, reeds, intakes, pipes, etc.etc.... I have gone down this road over this winter and have about $2000 give or take invested into building my 4mil long-rod... Quote Link to comment Share on other sites More sharing options...
Zillaguy Posted April 12, 2013 Report Share Posted April 12, 2013 Correct me I am wrong, but the 795 piston, the wrist pin is actually closer to the top of the piston, meaning the skirt will be closer to the crank. Reason people use the 795 piston is so you dont have to use a spacer. Hmmm... I was under the impression that the piston skirts would crash into the crank at BDC without them being 795 or running a spacer plate... Quote Link to comment Share on other sites More sharing options...
Zillaguy Posted April 12, 2013 Report Share Posted April 12, 2013 Think about it, longer rod means the piston will be 5mm higher at both tdc and bdc. That is an extra 5mm gap between piston and crank. So really, using the 795 piston makes it closer to the crank. Also a long rod doesnt mean it will be 5mm higher throughout the rotation. LOL sorry I had to draw it out on paper! I need visuals! Lol you are right... the 4mill stroker will put 2mm higher at the top, and 2mm lower at the bottom, coupled with a 5mm longer rod you need an offset wrist pin to make up the difference... Quote Link to comment Share on other sites More sharing options...
4mil89 Posted April 12, 2013 Report Share Posted April 12, 2013 The spacer plate goes in between the head and the cylinder and has nothing to do with bdc Sent from my SAMSUNG-SGH-I717 using Tapatalk 2 Quote Link to comment Share on other sites More sharing options...
trickedcarbine Posted April 13, 2013 Report Share Posted April 13, 2013 ZIllaFreak, the longer rods do increase dwell time though. Quote Link to comment Share on other sites More sharing options...
toytech Posted April 13, 2013 Report Share Posted April 13, 2013 The spacer plate goes in between the head and the cylinder and has nothing to do with bdc Sent from my SAMSUNG-SGH-I717 using Tapatalk 2 mine came with a spacer that went under the cyls Quote Link to comment Share on other sites More sharing options...
Zillaguy Posted April 14, 2013 Report Share Posted April 14, 2013 I have only seen the spacers that go between cases and cyls... Quote Link to comment Share on other sites More sharing options...
salmon_slayer06 Posted April 15, 2013 Report Share Posted April 15, 2013 I'm building a 4mm also. So far I did the shift shaft bearing install, shift drum bearing, and shift start mod. I still need to get the shift detent arm, modify the opening in the shift shaft and get my gears back from getting the dogs removed. Today I boxed up my cylinders and they are going to FAST to get ported. I'm just going with the woods port.... I'm a three year banshee newb. After my banshee rebuild, I can say I have at least some experience and have learned a thing or two. Watching the Silver Lake Sand Dune videos on you tube only makes the anxiety worse and I wish I had shipped my cylinders out a month ago. Well, time to order more parts.... Quote Link to comment Share on other sites More sharing options...
05colorado Posted April 17, 2013 Report Share Posted April 17, 2013 Just get a kit 4mil kit from one of the sites sponsors. I bought mine from HJR last summer and came with everything needed to run and they have options. Base kit is crank, cylinder spacers, pistons and full gasket set. This will get you running using all stock cylinders and head. You can skip the spacer and get a cool head with the proper domes cut for a 4mil crank. Next option is having your cylinders ported to match the stroker crank and riding style. Surf some of the sponsors sites and decide what you want to build. Mine is a woods/mx bike and runs great with plenty of power and loads of torque. Shocks my 4 stoke buddies every time we go riding. Quote Link to comment Share on other sites More sharing options...
Slayar71 Posted April 29, 2013 Report Share Posted April 29, 2013 So for a 4mil kit, would you stay with a stock rod or go for the long rod. What are the advantages and disadvantages? Quote Link to comment Share on other sites More sharing options...
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