hibby

I have a zenoah m-5 and purchased a stroker crank from gizmo motors and he doesn't say anything about using it in a modded cylinder and want to see if anyone else has put one in a modded cylinder to make sure there is enough clearance at the top of the jug. Dockman I think you said you put one in your modded cylinder, did you have to do anything to yours or have any issues? I might call bruce tomorrow at gizmo and check with him to be sure. Hibby

Dockman

I would have to look at my notes to see what thickness of gasket I used. I did have to use a thicker one I know that. I'll go look now and post up.

Dockman

I used a .020 copper gasket on mine but you will need to check. That give me an .012 squish.

Scott Schneider

Pretty basic math gives you parameters involved ... 1 mm = @ .040" which divided between 180 degrees of rotation is .020" lower and .020" higher than a stock crank moves, So looking at typical squish clearance a stock Zenoah has of @ .034" ... take away .020" at TDC leaves .014"
Now IF that is actually what you have ? it needs to be accurately measured.
For those tuning at more precise values the height of all ports and there "Degree" value need to be adjusted for the tuners perceived ideal value.

Or ... in novice terms, if it fits, don't hit and runs better/faster etc ... great

jtdesign

RLMAO scott,

it brings to mind the scenario of the "It will never fit[sm=cry_smile.gif] "wanna bet[sm=punching.gif]"[:-]

hibby

Thanks for the replys guys, I think tony's m-5 jug is shaved . 010 I will have to make sure. If that is the case that would put my top dead center at .004 . (stock jug squish clearance .034 minus .020 at top dead ctr leaves .014 clearance minus .010 for m-5 jug shaved leaves .004 clearance) is that correct scott? If I have to use my stock jug with the stroker crank and not my m-5 jug I am wondering if it is even worth putting the stoker crank in. Hope Im not sounding stupid but trying tio learn some of these things. Thanks Hibby

jtdesign

Did you take these measurements with a dial indicator thew the spark plug hole. if not you will need to. I think scott was just giving you what the numbers that are suppose to be.

Scott Schneider

Yes, numbers shared were just averages ... ABSOLUTE clearance YOU HAVE must be measured prior to final assembly / set-up.

Dockman

Hibby YES you can use your m5 cylinder. You just need to check your squish to see what base gasket you will need to use.

hibby

dockman, I talked to bruce at gizmo and he said I would have to have the base of the jug turned down or the ring is going to go to far down past intake, which Im confused now, because whats the purpose of the thicker gasket then. Give me a call if you get a chance ph 704-633-6039 if you can't get me leave me a message and I will call you. thanks hibby

danielplace

The only way you will no for sure if the ring going below the intake roof is to set your squish and rotate to bottom dead center look in the port and see. You will probably be fine unless more material than just the nub was removed when the jug was modded and I am pretty sure the intake roof height on a M-5 is not raised. Best of luck. Should be fine.

hibby

Me and a friend are going to work on it tonight and I will post what we find out. Tony at whh said that he doesn't touch the intake on the m-5 so it shouldn't be raised.

hibby

Dockman did you have to do any porting with your stroker crank? Are you using that top end rcmk eco cylinder kit? hibby