Building a 10mil stroker on stock cylinder

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TN-592
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Joined: Mon Jan 11, 2016 6:48 am

Building a 10mil stroker on stock cylinder

#1 Post by TN-592 » Tue Apr 11, 2017 9:12 am

I am interested in starting this project cause I have a free work shop machining.To do this I need to make a new sleve so please could you share your thoughts and ideas about proper ports tuning for a 10mil stroker

justind97
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Re: Building a 10mil stroker on stock cylinder

#2 Post by justind97 » Tue Apr 11, 2017 10:27 am

Go take a look through the build threads on BansheeHQ those guys build these all the time.

TN-592
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Re: Building a 10mil stroker on stock cylinder

#3 Post by TN-592 » Wed Apr 12, 2017 9:10 am

So it looks like there is not to much data about stock 10mil.....
I have compared cheetah cub 10 mil ports to a stock 31k and it look like it will not be problem to make a slave with a same ports as cub and ajust it to a 31k cylinder but the slave will need to protude 5mil over the top of the cylinder....then I was planing to put a 5mil plate between the top of cylinder and a head so i don t have to mill the head....
I will post some pictures in a about two weeks when my new crank arrives

justind97
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Re: Building a 10mil stroker on stock cylinder

#4 Post by justind97 » Wed Apr 12, 2017 1:52 pm

Adding the plate only messes up the port timing more and you will not be utilizing the full extent of the stroke.
You're better off machining the head to fit. I believe with the +10 it will require epoxying the cases. I may be mistaken, but I think I remember +7 be Big as big as you want to go.

Contact TDR, he'll point you in the right direction

TN-592
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Re: Building a 10mil stroker on stock cylinder

#5 Post by TN-592 » Wed Apr 12, 2017 2:47 pm

I don t intend to rise cylinder with a plate a want to put a plate on the top of the cylinder around the sleve which will pop up 5mm from the cylinder so I could use normal head gasket

evan_calgary
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Re: Building a 10mil stroker on stock cylinder

#6 Post by evan_calgary » Wed Apr 12, 2017 3:08 pm

Sounds like a big waste of machine time that could be used doing something productive. The 10+ mill cyls ain't cheap but probably a better choice than this disaster...

Feel free to prove me wrong...It would be nice to see you succeed I just don't see it.

TN-592
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Re: Building a 10mil stroker on stock cylinder

#7 Post by TN-592 » Wed Apr 12, 2017 3:40 pm

I have been reading about 10mil stock from banshee forum and some of the guys has seen it in action and they say it absolutly rips.....so that why I decidet to try it out......if it dosent work I don t mind

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JanBros
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Re: Building a 10mil stroker on stock cylinder

#8 Post by JanBros » Fri Apr 14, 2017 8:02 am

been reading for some time on this forum to get to know the engine, as I am going to build one myself to put in a KR1. I have everything for over a year now, but other projects keep getting i the way.

I'm going to build a +7mm with 64/64.5 bores. Would have liked a +10 as a good 2-stroke engine should be as square as possible but feel like it requires to take too much metal from the crankcases to make room.

I'll be using original Banshee cylinders (it's for a trackbike, I don't care about powervalves giving more bottom end) and have bought blank sleeves (no holes) from LA-Sleeve (FL64) so I can make my own timing. Main point for blank sleeves is I can leave a bridge in the exhaust port and make a double V-style port going much wider at the top.
I will let the sleeve stick out on top of the cylinder by 3mm so the piston comes flat with the sleeve at TDC and mill my own head to except the sticking-out sleeve.
if it runs, you can race it !

TN-592
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Re: Building a 10mil stroker on stock cylinder

#9 Post by TN-592 » Fri Apr 14, 2017 5:35 pm

It would be a interesting build,how are you going to put a head gasket if you dig a head?
I was also planing to make a v shape exaust all the racing bike has one

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JanBros
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Re: Building a 10mil stroker on stock cylinder

#10 Post by JanBros » Fri Apr 14, 2017 5:56 pm

TN-592 wrote:It would be a interesting build,how are you going to put a head gasket if you dig a head?
gasket ? :smt018

any 2-stroke of mine is O-ringed :smt002
if it runs, you can race it !

TN-592
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Re: Building a 10mil stroker on stock cylinder

#11 Post by TN-592 » Fri Apr 14, 2017 6:12 pm

To be honest I've never seen a o ring between cylinder and head,from which material,cooper?

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JanBros
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Re: Building a 10mil stroker on stock cylinder

#12 Post by JanBros » Sat Apr 15, 2017 6:14 am

TN-592 wrote:To be honest I've never seen a o ring between cylinder and head,from which material,cooper?
viton rubber

Image
if it runs, you can race it !

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