Topic: alcohol carburetor

[Mark Karlsson]

Hello. 

I have a single overhead cam Honda 750 drag bike, turbocharged and I'm thinking about running it on methanol.  I currently use an SU carburetor. 

Does anybody know of a carburetor I can use that would have adequate flow to be used with alcohol (methanol)? 

9.10 at 146 MPH  -- currently looking for more horsepower! 

Thanks.

Mark Karlsson

[Sam Green Racing]

Welcome Mark, back in the day, most of the top supercharged bikes in the UK ran SUs.
As a starting point, just double the main jet, it's very difficult to be to rich on methanol but being to weak will end in the same results as being weak on petrol.
Make sure there are no plastic or rubber components in the carb as methanol can damage some of these components.
How about some pictures and what is your location?

Sam.

[johnny_from_bel]

Dubbeling the Jet size is obout correct.


Please not that the following is purely theoretical. I have never done it myself.
Use your own jugement on this !!


Stoichiometric air-fuel ratio of

Petrol is 14.7  1
Ethanol is 9:1
Methnanol is 6.4 : 1

Wiht that you can calculate the jet size

Sp = ratio for petrol
Se = ratio for ethanol
Js  = Current Jet Size
Jn  = New Jet size

Jn=(Sp/Se)*Js

Eg for Ethanol

14.7/9*current Jet size.


Hope this helps a bit.

[kos]

Hello. 

I have a single overhead cam Honda 750 drag bike, turbocharged and I'm thinking about running it on methanol.  I currently use an SU carburetor. 

Does anybody know of a carburetor I can use that would have adequate flow to be used with alcohol (methanol)? 

9.10 at 146 MPH  -- currently looking for more horsepower! 

Thanks.

Mark Karlsson

Mark

Order up a set from me and they will have all jetting changed over to run alcohol. CR Specials. 29, 31, 33 & 35mm.

Mark @
KOS

[Sam Green Racing]

It would have to be a big one Mark, he only wants 1.

Sam.

[Sam Green Racing]

I guess the thread starter wasn't really bothered about an answer

Anyway, I did a bit of digging and if he deceides to go the whole hog, he can expect it to run mid 7s

http://forums.dragbike.com/forum_posts.asp?TID=14706&PID=191867#191867

Thanks Big Jay.

Sam.