Help with my big bore project!!!!

Ok I'll try and keep this short. I'm doing a 94mm bore, on my 400S, through MT and running RHC cams so I can put in my stroker next year. The problem I have run into is that MT doesn't offer a Compression Ratio high enough to keep the bottom end on the bike with a 94mm kit. The 94mm comes with 12: 1 CR. I need 13 or 13.5: 1 to keep my bottom end for trails and run pump gas for all of the commute?. How can I get a good enough compression with the 94mm bore to keep the bottom end? Should I just go through Lukes and build the kit with individual components, adding the high compression piston?

How can I get the higher compression with the smaller bore? The 94.5 and 95.5mm bores come with a 13: 1 CR, but not the 94mm. Nate, Ed, somebody........ HELP!!! Reply to this message or email me at or call me at 865-898-3590. Your help would be greatly appriciated in getting this matter ironed out so that I can build my motor.

if you absolutely have to have the 13.5 to 1 you need to go 94.5mm or machine the cylinder base .020".

that will require cam degreeing.

I don't absolutely need 13.5: 1. I just want to keep the bottom end on the bike. I do much trails in the mountans and lots of street commute on the highway. I want a better top end and to keep my bottom end with the 94mm bore. Next year I'll be having Dave do the work to an LTZ crank that I have for the stroker project.

Basically I want a compression that is going to be high enough to let me keep the bottom end and not so high that I run into a lot of money. SO the highest compression that I can run with a 94mm bore and RHC cams and no excess work.

This is close..

the big bore itself will keep plenty of bottom end.

i have a Athena kit for sale if your was on a motor,but never fired.

i will sell it for dealer cost.

If KVO doesn't want it I might be interested.

PM sent Ed.

the big bore itself will keep plenty of bottom end.

i have a Athena kit for sale if your was on a motor,but never fired.

i will sell it for dealer cost.

So the big bore with RHC cams will run a good bottom at what compression? Remember I still want to run 93 octaine.

Ed, I PM'ed you about the kit. I'll probably take it if the price is right. How will you do on a trade for an LTZ motor that I have dismanteled? I wrote a post about it a while back and you said it may have had an oiling problem. The Cylinder is what I have planned to send off and the crank was going to dave for the stroker work..........but............. if you want you can call me at the # I posted above. Also when I have the stroker built, You will do the work. As long as I can get one of those custom "built by burned" plates for it.

12.5 to 1 will have plenty of bottom end.

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