Random carb idea/question for you.

[zore]

I use the rear brake infrequently.  Just a habbit i picked up doing track days on bikes with better brakes.  This is why it's important to me to make the front brakes as good as they can be and I still have some work to do.

[Glyn]

Blake - I have sent you a pic of my Weber IDF carb conversion. Let me know if you need details of the manifold construction.  ;)

[hmmmnz]

sorry for dragging up an 8 year old post :D
but ..... im thinking i might have an attempt at doing a single carb conversion,

any one got any tips before i begin :D  (apart from don't bother :D )

[Walt_M.]

Aside from asking why? Are the originals too messed up to fix? Anything is possible but what is your motivation? I say go for it if you want to but have a caution if you have to pass emission testing.

[RedRocket]

sorry for dragging up an 8 year old post :D
but ..... im thinking i might have an attempt at doing a single carb conversion,

any one got any tips before i begin :D  (apart from don't bother :D )

I'm sure there is a recent member on here who HASN'T changed his/her brake rod bolts.

[hmmmnz]

yeah ive changed them now :D  gee  (thats a pretty good memory)
no there isn't anything wrong with my carbs, starting a bit hard, but nothing unusual,
i just like trying new things :D

the only thing im worried about is the 2 different jet settings to keep the rear cylinder cooler,
i might try have a shorter distance to the rear intake,
i think ill make out of copper first, and maybe make a few and see what runs best,
then make one out of stainless later if i ever get it running decently :D

[fret not]

I discussed this idea with Craig at Hanson Race Technology in Chico CA.  His thinking was to reshape the intake ports  and use some less restrictive carbs, like DelLorto which flow so much better than the Mikuni "Webers" that come stock on the Vision, plus they are some of the least expensive good carbs.  This would not be a bolt on remedy, as there would need to be some welding and machining to the heads to re-angle the surfaces that the carb mounting boots fasten to.  There are other possibilities but they also need some fabrication and ingenuity.

[hmmmnz]

hmmm, might be worth getting a whole new engine, to wreck :D  they are a dime a dozen here in nz
amazing number of the 400's made it here, good ole free trade between nz and japan does that i suppose,
ill give the single crab idea a go without changing anny of the ports, if i get favourable results ill go further with it,
im just wondering on what size carb and intake to go for

[Walt_M.]

The different jetting is not to keep the rear cylinder cool, liquid cooling does that, but to compensate for the different exhaust pipe length. You probably shouldn't put anything over 40mm on it. And the end result will be a bike that probably won't run as well as a well set up stocker. But, have at it if it makes you feel good. 

[Cdnlouie]

I don't want to discourage anyone from doing something they would like to do or because it just hasn't been done yet, but this single carb conversion sounds like an approach that takes 3 steps back, to take one step forward.  As has been noted by others there is too much to lose: such as lower performance, much more than the cost of a decent 82 rebuild, and a ton of work.

I have rebuilt a lot of 82 carbs and have had nothing but decent success.  I have found lots of screwed up carbs from past botched jobs and rusty tank debris clogging jets, but never a bad set of 82 carbs.  My own set (my first ones) I rebuilt about 9 years ago and have not touched them since.  I remember doing the carb update on the new 82's and taking her for a spin down the road and it was no slouch, a solid performer with the stock setup.  Unfortunately, you can save yourself a lot of headache if you just get the carbs sorted right at the beginning and you are golden  ;).

I don't discourage new innovations for anything and a single carb setup might have its application on a Vision, but I would definitely go with the fuel injection idea and make some progress there as that would be very nice on a Vision (Get on it Ken...a great retirement idea for you).

Enjoy the new riding season everyone,

CDNL

[Glyn]

Hi All, I've said all of this before, but I went down the road of trying to get my standard carbs to run correctly but just could not. I looked at the various options of alternate carbs, but figured that Yamaha had nutted all of that out so why re invent the wheel. Cruising through the local trademe site I saw a carb that looked almost identical to the Mikuni. A weber IDF carb. They have been out for ages and are a performance modification for various downdraft applications. They are put onto Harleys and Goldwings and those big boys suck plenty of fuel. The main advantage over the Mikuni is ease of jetting, better materials and just plain reliability. I've had my conversion of for a couple of years now. Never cleaned the carb and it just never gives me any hastles. Making the manifold is the most time consuming item. Mine was a one off  which I machined up myself. Any decent engineering shop could improve on my efforts I'm sure.
You whack open the throttle and it just rockets away, no lag, no stutter, just like the Yam R&D man envisaged. He should have bought more pizza.