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What do you think? useful or not?


Spqreddie

Well Known and Active Website User
VOC Member

he UFO is a simple, trouble free, aerodynamic piece that fits VM Mikuni carburetors from 30 mm through 44 mm. The UFO makes a normal round slide carburetor out-perform the more expensive flat slide carburetor by eliminating turbulence and increasing air flow and velocity, creating a highly atomized fuel charge. Normal gains are 3/4 to 1 HP per 100 cc of engine displacement on 4 stroke engines and 1 1/2 to 2 HP per 100cc of engine displacement on 2 stroke engines. (Minimal rejetting and tuning are required).
 

BigEd

Well Known and Active Website User
VOC Member
VOC Forum Moderator

The UFO is a simple, trouble free, aerodynamic piece that fits VM Mikuni carburetors from 30 mm through 44 mm. The UFO makes a normal round slide carburetor out-perform the more expensive flat slide carburetor by eliminating turbulence and increasing air flow and velocity, creating a highly atomized fuel charge. Normal gains are 3/4 to 1 HP per 100 cc of engine displacement on 4 stroke engines and 1 1/2 to 2 HP per 100cc of engine displacement on 2 stroke engines. (Minimal rejetting and tuning are required).
Oldhaven made the post below in April 2018, perhaps he may have more information on his findings now.

Cyborg, On my similar Comet project I will be using the same ignition system and a 36mm Mikuni with UFO as recommended and set up by Steve at Motocarb. I was going to go smaller but Terry Prince recommends a 38mm for his top end and Steve seemed to think a 36 would be a good choice. Here is a picture of the UFO, and as you can see it required a bit of machining on the slide and apparently in the bore, but I could not tell where that was done. Motocarb set it up for the changes with jetting, but included some extra sizes so it can be fine tuned when I eventually get it on the road. I bought the large intake bell they offer, but may or may not use it and fit a filter instead. I may make some sort of screen for it to keep out the sparrows.
 

Oldhaven

Well Known and Active Website User
VOC Member
I'm afraid I won't be able to say much one way or the other about the device until next year since my Comet project is mostly on hold until we get into our new house and I get my shop and tools out of storage. (You will win the race on this one, Bill). Even then I won't be able to judge the truth of the claims made for it since it will be on a new 600cc engine with no history. For that you would need to talk to someone who did a before and after comparison. It does appear to be nicely made and fitted and I decided to take advantage of Motocarb's experience in fitting and their tuning and jetting recommendations since I needed a carb for the project. They did send some extra jets in case I need to play with things. We shall see.
 

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