I'm in the process of converting two 25cc engines from two xt250 model Weed Eaters. They are to be install in my next project, which is a Don Smith A-26 that I hope to get started on in the Spring. I do have a question on the Carb, since this is the first time that attempting to do this. The carbs sticks out too far and
I would like to move them closer to the engine so that they fit in the cowls without losing half of the cowls. Is this possible? How do I go about it?
Have a look at the photos and you'll see what I'm referring to.

Hello,
You can make a new insulator as thin as 3/8" from G10 epoxy board or some other insulating material. You need some space between the cylinder and the carb to prevent vapur lock. It is difficult to cut down the existing insupator because its depth is needed to hold the carb on. Lose the air cleaners.

Dave

Hi Dave:
thanks for the info, I do plan to get rid of the air cleaners will post new photos in a while to show progress.

here are a few more photos showing just how far I've got. After performing a closer inspection of the carb base, I note that it is possible to cut it down to 1/2" or 3/8". Will try it and see how it fits, 1/2" first an then to 3/8" if nesessary. Hope it works.

take a close look at the factory position of the throttle shaft............ for me a pain getting alignment going aft. (This position thing may be all wrong, I thought this was a homelite engine.)
Dave's suggestion to make a new makes sense to me. Have the material just haven't done it yet. First attempt was making an additional twister plate of alum. and that added needless weight.

Are you using a stud in the front part of prop hub thru the prop and threading into the alum 'spinner nut'?

Loose the centers of the mounting bracket/plate...

Which version? http://www.donsmithplans.com/

Have you searched thru Engine Conversions for info? A lot of data and tips.