my dad told me for xmas i can buy all the part i want for my bottom end of ebay. so ive been looking and i found the 4mm crank but it appears i have to get alot of work done to make it fit so im going with the 3mm crank. do i have to have any work done to the head jug or case to put the 3mm crank. and please recommend any bottom end parts i should get
help with 3mm crank
- Thread starter 01blaster
- Start date
It was actually in freek'n'bat's two new rebuilds. You need to do some filing at the top of the cases and you can either take some metal out of the head, or use the provided spacer plate if you buy the full kit.
yea you will need to have you case trenched for the 4mm and you need head work dont .. for the 3mm it hits just a little bit so the case will need to be filed down some so it dont hit, and with the spacer they give you should send your cyli off to have the ports matched ..
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Yeah the 4 needs to be trenched but the 3 also needs a little filing around the top of the case's where the rod comes out and goes up into the piston. It hits when the rod is going in to the up position. It's no big deal though, you can do it yourself with a hand file in just a couple of minuets.
Other Than the crank, I would get all new seals, Bearings, A barnett clutch set, and a billet clutch basket. And remember what ron89 said, if you get the crank you have to have your ports matched to the crank. They will send you a spacer with it, to help but its not good enough. it still needs more work. Flotek fixed mine for me and did a great job.
Other Than the crank, I would get all new seals, Bearings, A barnett clutch set, and a billet clutch basket. And remember what ron89 said, if you get the crank you have to have your ports matched to the crank. They will send you a spacer with it, to help but its not good enough. it still needs more work. Flotek fixed mine for me and did a great job.
is there anywhere to buy the bearings online? all i can find is the crank bearings. i already have all new seals. i am going to do the 3mm crank and get my flywheel lightened and some mods done to my shift star. i cant find anything else to do to the bottom end. can anyone give me a good website for flotek or a company to send my top end to to have the ports lined up.
heres my question....I have the 3mm crank in my bike with .90 over piston and it seems to be just fine. what is all this having your ports lined up stuff that everyone is talking about.?
my cylinder is already heavily ported for MX. What happens if I install the +3 crank, but dont get any ports touched up??
the motor has hardly any lowend, but once it gets on the pipe it rips. so a boost in lowend would be great!
(PT pipe/silencer, 34mm PJ(?) Keihn carb, boyesen reeds, FUJIMO MX porting/high compression, custom airbox to carb boot, 14-38 gearing)
the motor has hardly any lowend, but once it gets on the pipe it rips. so a boost in lowend would be great!
(PT pipe/silencer, 34mm PJ(?) Keihn carb, boyesen reeds, FUJIMO MX porting/high compression, custom airbox to carb boot, 14-38 gearing)
with the added stroke the piston is moving up and down farther in the cylinder..therefore the ports need raised and lowered to open at the corrct times to maximize power...
and yes even if it is already ported for MX or whatever style of riding/racing....the ports will need adjusted to the added stroke/movement of piston.
contact : www.flotekperformance.com for the bst porting services.
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