Carby GT5 GEN 4 80cc: Rich or is this normal?

It does look like you are a bit limited in what you can do. I know with my jack shaft the engine didn't quite sit how I wanted, So I used a spacer on the bottom part of the back mount. In between the curved part touching the frame and the plate mounted to the motor. Which will help tilt the motor. If you have the flat part of the mount that comes with some of these kits "for the drilling the frame engine mount" that will work perfect, with some drilling.

With that much of an angle it's doubtful it will correct it entirely, but it may help enough. And it shouldn't effect your clearance to the top tube by much. I'm not sure I would go more then a 1/4", but even an 1/8" should help.
 
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You are on a pretty good angle, it's enough that the float adjustment is going to be sensitive. I don't have a shift kit (whaaa) so I'm not sure if you can shorten the jackshaft to front sprocket chain with a half link and rock the back of the motor down a little or not. I guess if it gets alot worse going down hill and better running going up hill that would be a clue. You may just need to tinker with the float a little.
 
Hmm thats actually a pretty good idea Shadeslay I might have a bit of a play with that. The motor actually stuggles going up hill and is good down hill but now that I think about it it does run smoother when going up a slight incline. I have an expansion chamber and boost bottle on order so once they arrive I might have a tinker with it all.
 
Ok. I have followed Shadleslay's advice and spaced out the bottom mount which has made a slight improvement to the angle of the carb. As well as that I have now moved the needle clip up one notch, changed to premium fuel at a 25:1 ratio with synthetic oil, fitted a NGK BP6HS spark plug and fitted the SBP expansion chamber which came in the post :D
The bike is definately running better now and accelarates alot harder and sounds great. However I havent really gained any top speed and the bike seems to have the same problems trying to rev as it did before. Im sure it has way more in it especially in top gear. If you open the taps it stops running smooth and sounds like its missing and gradually looses power. Its goes from a nice brrrrrrrrrrrrr to a bap bap bap bap if that makes sense and like before it struggles to recover unless you really back off the throttle. It really seems like it wants to go much harder but it just reaches this wall and dies in the arse. In someways it is a bit like a rev limiter on a car.

ps: top speed is about 40-45kmh assuming I set my computer up right :)
 
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what i did was run my engine 14:1 for the first 500km(the manual said 16:1 for 500km) and then i leaned it out to 20:1 which i curently run 3000km later, i sugjest just sticking with the rich mixture until the break in is done,
 
I ran 7oz oil the first gallon, 6oz the 2nd gallon & now I'm 5oz per gallon (read that mixture in a thread) I don't have a speed-o that works right, so I don't know how many miles I am getting per gallon? How does your motor (engine) motors are electric. Run? Did you change the needle setting?
 
I ran 7oz oil the first gallon, 6oz the 2nd gallon & now I'm 5oz per gallon (read that mixture in a thread) I don't have a speed-o that works right, so I don't know how many miles I am getting per gallon? How does your motor (engine) motors are electric. Run? Did you change the needle setting?

when i ran it rich for the break in there was ALOT of visible smoke and oil caked the chasis, performance was poor and it wouldent idle. it stalled and fouled plugs. it slowely began to run better after the 150km mark, then i weened it to 15 or 16:1 and it kept getting better, i actualy probably went to 20"1 after around 300km and it kept geting better and better until 500km when it ran perfect, i have left the needle in the stock half way down position, trust me, the engines run like **** while they break in but it will get better, how many km do you have on it so far?
 
I don't know how many miles I have on it yet (no speed-o) It runs really good now, on my 6th tank of fuel (about 3rd gallon). Can only guesstimate @ 100-150 a gallon maybe 300-450 miles, I'll say the lesser because of hills & wind conditions. I just received a slant head & gasket. Going to install this week end if I get the time, also have a speedometer on order. after every thing is installed, I"ll see how it goes!
 
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