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Drained

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Discussion starter · #1 ·
Ok, Need some of you motor guys to help me out.
I have a 108 Honda motor built like this:

TB 51mm stroker crank
Takegawa 88 cylinder
Older style F5 Takegawa super head
Tak special clutch

My question is, can I make this motor a 117 with keeping this head and crank?
If so, please tell me how. I know I could just buy the TB117 kit, but I'm trying
to re-use as much of the parts that I already have if it's possible. Can I just buy a TB 54mm jug and piston
to work with this head, then just bore the cases and be done, or do I need a special cylinder and piston
specifically for this head?

Any help/advice much appreciated. Thanks.
 
#5 ·
Drained said:
Ok, Need some of you motor guys to help me out. I have a 108 Honda motor built like this: TB 51mm stroker crank Takegawa 88 cylinder Older style F5 Takegawa super head Tak special clutch My question is, can I make this motor a 117 with keeping this head and crank? If so, please tell me how. I know I could just buy the TB117 kit, but I'm trying to re-use as much of the parts that I already have if it's possible. Can I just buy a TB 54mm jug and piston to work with this head, then just bore the cases and be done, or do I need a special cylinder and piston specifically for this head? Any help/advice much appreciated. Thanks.
Click to expand...
Yes you can keep crank and use a tb 54mm jug and slug. You will need the crf 50 v2 piston though with that head. the tb V1 race head piston will lower compression plus valve pockets will absolutely need machined for the larger and flatter valve angle of the takie head. Also as Longmooie has stated to jump up into the 54mm bore cases will have to be bored for the larger sleeve. That is your cheapest alternative.
 
#6 ·
[h=1]TB 790 Piston 54mm - 117cc XR/CRF50 XR/CRF70 RH V1 and V2
Part No: TBW0790
Location: 219D[/h]


Performance Piston Kit
54mm w/ 13mm wrist pin kit includes rings ,pin and clips
For use with TB 54mm x 63mm cylinders
All 88-Present 50/70 using stock or tb stroker crank and tb race head V1 or V2

 
Discussion starter · #7 ·
storminnorman07 said:
Yes you can keep crank and use a tb 54mm jug and slug. You will need the crf 50 v2 piston though with that head. the tb V1 race head piston will lower compression plus valve pockets will absolutely need machined for the larger and flatter valve angle of the takie head. Also as Longmooie has stated to jump up into the 54mm bore cases will have to be bored for the larger sleeve. That is your cheapest alternative.
Click to expand...
Thank you Stormin..
So just to sum up. As long as I use the newer V2 piston, I can use my Tak super head without any modification. Bore the cases, add the 54mm jug, and I'm good to go..?

Thanks Vince for posting the piston kit. I'm all over it..
 
#8 ·
Drained said:
Thank you Stormin.. So just to sum up. As long as I use the newer V2 piston, I can use my Tak super head without any modification. Bore the cases, add the 54mm jug, and I'm good to go..? Thanks Vince for posting the piston kit. I'm all over it..
Click to expand...
Np happy to help. Yes as long as you use the xr/crf 50/70 V2 54mm piston (the one Vince posted) It will work for you. The V2 head is very similar to a takegawa +R head. valve angles are similar, intake valve head diameters are the same 28.5mm, exhaust valve head diameters are the same 23.5mm. The old super head and the newer +R head are pretty similar the older super head that you have comes with smaller 27/23mm valves if I recall correctly. so the valve pockets and dome shape will work with the superhead you have. I do want to point out one other thing cause this seems to be a reoccurring issue I have seen. With that TB crank deck height will be pretty much zero deck so do not jump froggy and go screw this thick head gasket that TB supplies with the kit and say I'm using a thin spring steel type gasket. I can assure you it won't take long before you wish you hadn't decided to do that. The thin spring steel gasket is right around .010"~0.012" thick. Deck height with that crank, 63mm tall cylinder, compressed base gasket and V2 piston will yield a deck height of 0 +/- 0.005". With that said you will only have between 0.005"~0.017" quench clearance. When you factor thermal expansion and rod stretch piston will wrap the head. So I will repeat use the thick head gasket that is supplied with the TB 54mm kit. Other than that yes simply bore your cases, pick up a 54mm V2 bbk grab yourself some adult beverages and get to wrenching ;-)
 
#12 ·
Drained said:
Sorry Stormin', So thats a yes or a no on the TB117 gasket kit? Are you saying there is a thin and a thick one , and to use the thick one? sorry just a tad confused..
Click to expand...
Sorry to confuse you. I'll try to clear it up. When you purchase the Tb 54mm V2 piston/cylinder kit. it comes with a thick composite head gasket. You want to make sure to use that gasket set. What I have noticed a lot of guys trying to do lately is they want to achieve more compression so they try to use the thin spring steel type head gaskets in place of the thick head gasket supplied with the kit. So in my previous post long story short don't do that. If you do the piston will kiss the head when engine is operating resulting in one hell of an expensive aluminum paper weight. Make sense now?
 
#14 ·
[h=1]TB 54mm Head Gasket Kit 117cc
Z50 CRF50 XR50 & Pit bikes
Part No: TBW0318
Location: 219I[/h]


Replacement Gasket Kit for 117cc Bore Kit
TB 54mm Head Gasket Kit [TBW0318]
Fit Pit bikes with Honda stud pattern and 54mm bore

 
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Drained
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