7 replies to this topic
  • MXH

Posted September 28, 2001 - 06:44 AM


I'm having trouble getting hold of a standard 12.5 to 1 piston, but can get hold of a 13.5 to 1 compression piston. Has anyone tried the 13.5 to 1 ? Any other changes required? Does it make any difference?


  • yzernie

Posted September 28, 2001 - 09:53 PM


Originally posted by MXH:
I'm having trouble getting hold of a standard 12.5 to 1 piston


Are you talking about a stock piston or any 12.5 to piston???


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  • MXH

Posted October 04, 2001 - 02:00 AM


Well, I was referring to the difference in compression ratio, but are you going to suggest a difference in different makes of piston as well?


  • SFO

Posted October 05, 2001 - 02:54 PM


I am running a 13.5 to 1 97mm wiseco.
After setting the deck height/squish with 22cc of chamber volume the static compression is around 14 to 1.
The other changes include putting grip tape on the seat cover so I can hang on!

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  • MX_Tuner

Posted October 06, 2001 - 06:28 AM


SFO, what fuel are you burning? What gearing are you running? I had to go up a tooth on the front to be able to use first gear at all.

Ain't that motor wonderful?

MX Tuner

  • SFO

Posted October 06, 2001 - 06:43 AM


I am reading right out of Riches bible. Thank you for hooking me up with him.
The bike is on the dyno right now.
I am comparing strait B37 to B37 with MTBE and am also running some unleaded nutec to see how it compares.
I am also running a Arrow pipe and the falicon cam sprockets set at intake 105 lca and exhaust 106 lca.
I also took 50 grams out of the piston/wristpin. The dyno will tell if I made stuff too light...
I also brought all the needles from TT and JD.
Dale Lineaweaver, (my friend with the dyno) laughs and pulls out a box that has at least 500 needles in it. He says that he thinks he has it covered.
Dale is looking at the 97mm setup for a husaberg to contest his Pace championship.
Yup, this thing flat out hauls the mail.
I will post the #'s as soon as I know.
I hope it lives.
Oh yea, midrange hit is too mild a description for what this thing does.
I am still running my woods gearing, 14-52.
now the first two gears are unusable.
It reminds me of my old yz490, keep the bike in a taller gear than you think always, or end up on your head!

[This message has been edited by SFO (edited October 06, 2001).]

[This message has been edited by SFO (edited October 06, 2001).]

[This message has been edited by SFO (edited October 06, 2001).]

  • MX_Tuner

Posted October 06, 2001 - 04:12 PM


Remember what they say: "Too much horsepower is *just* enough".

MX Tuner

  • SFO

Posted October 08, 2001 - 01:24 PM


52 dynojet rear wheel hp.
will post the chart if you are interested.
The arrow pipe is great!
I will post the db #'s tommorow.


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