how do you identifie the size of a carb? is it the inside bore on the engine side of the carb? Im going to the local motorcycle salvage yard and look through the hundreds of carbs and if one looks like a mikuni or lectron in good cond. that would work for the DS I wana determane the bore B4 I go any farther. also has any one used smaller duel carbs in stead of the big 39s? or is the 39s the most optimal for power increace through out the whole power range?
thanks
Sam

 

Sometimes it is stamped on the carb body, but not usually. Be careful, the carb manufacturers like to call, for example, a 29mm carb a 34mm. Measuring a carb at the engine side throat doesn't give the whole story. Many of these Mikuni and Keihin will neck down to an oval that measures 5 or 6mm less than advertised, at best. But if you measure the narrow part of the oval it can get worse.
I don't know of any motorcycle/atv/dirtbike that would come with a carb large enough to work on a DS, so I think you are wasting efforts at the salvage yard.
I have a mikuni 44mm roundslide brand new that I have never installed because the lectron worked so well. If you want to try it, you can buy it cheap, but it may take a month of jetting to get it right, because I never messed with it.

222

 

he has road bikes there to harleys and such, so I thought I might come accros a non bsr 42, 45 there or some thing hes got alot of carbs I was gona take my mic from work w/ me. maybe some of the fourm members could let me know what their ,44,45,46, 48 carbs mic out B4 I go over. I got the stock carb I can mic. I gess I could go by that reading, any thing bigger might be worth checking out.