Carb Re-location

Back on topic haha...

If your carb DOES fit in the origional posision ( not aimed at you Mexiacano! ) Is there any actualy performance differnces or gains from having them mounted read facing?
 
SaTaNaSsO:

Which would be the effect if not using the central frame as yours?

subframe015xr.jpg


Look at mine, it doesn't have it:

DSC02761b.jpg
 
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I think the difference would be noticed in corners. The engine unit flexes a bit from side to side even in stock frorm. With the more reinforcement it will likely be more rigid and result in less lateral movement and be stronger over time. Your construction looks strong but the mass of your scooter and you going around a corner at speeds will test it's limits!
 
You've been riding it around like this right? How does it feel? If you ride a crowded city most of the time a person doesn't get a chance to take corners very fast. Take it out at night when traffic is less or find a curvy road. :) Maybe it's up to the job!
 
Brookespeed:
I had the chance to drive it hard at corners and do not feel any difference but I can feel a little bit more vibrations compared to the engine when it was stock.

Do you think if I add the cross member the vibration would be less?

Thanks again,
 
great brokespeed!!! i would say the same things... but i must add another thing...
the subframe of mexicano is quite good, but the mainfold is too much long!!!
with the subframe that i posted u can put the carb with a shorter mainfold, that is better for your engine...
 
SaTaNaSsO:

The main reason my manifold is long is to clear the starter motor, I know it is better to keep it short but with a short one I can't keep my starter....and i want it.

CarbStarterMotor.jpg
 
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Mexicano said:
SaTaNaSsO:

The main reason my manifold is long is to clear the starter motor, I know it is better to keep it short but with a short one I can't keep my starter....and i want it.

Click to expand...

Performance depriviation? Yes...
Mexicano = happy? Yes! Not everyone wants what we want, But i can say, if i was doing it, id rather ditch the starter motor... The reason being, You can hardly see the startor motor from more than a couple of meters, and id rather have the performance!

But everyone for their own!

Nice work mexicano :)
 
lilplaya_bm said:
y in the hell does everyone want to do this with minarelli engines????with this wig thing u are getting a longer manifold then a stock version manifold which will take power and throttle response away from the powerband...i uhe the mhr short manifold for big carbs with my 24mm oko... alot of people cant do this because the carb would hit the cil..but if u cut a flat piece of aluminum, cut the center out, drill some wholes for it to bolt down, then drill outher wholes and thread them so the mhr manifold can bolt on but sideways thencarb wont hit cil...i did this and it works...and it is way better then a long manifold faceing backward....i have also tried long manifold(not with wig but a hommade one from aluminum- pics on my project)...it didnt run aswell as the short one...i gives me a way harsher powerband which starts at lower rpms....just a thaught...
Click to expand...

in my opinion you are right, i think the wedge thing is more commercial and customer dont think of the inlet! I have also mounted it above cylindre! Not a perfect location, but best in this situation...
 
Changing motor mounts often will make the vibrations increase. They are designed to work best in the their original form and any change will likely shift a load from one part to another and possibly alter the balance of the system. It may be putting a different load on the part of the motor mount that comes in contact with the frame. You could try putting different rubber buffers at this point. It could be reducing the effectiveness of the rubber/eurethan motor mounts that are on the engine cases. The engine is supposed to be able to pivot in that mount on the cases and if the forces are now coming in at a different angle due to the 2 new mounting points that have moved. It could be several things. More reinforcement could fix it, or make it worse. I would try one little reinforcment at a time, like just finding room for one 'sway bar' type support and see how it feels. you can always cut it back off. The buffer at the frame is likely more challenged as well. maybe you could cut a peice of an automotive motor mount and make something that would dampen the vibes. I put a 125 honda Lead 2 stroke engine in a Lead 80 frame. I made spacers so the motor mount would fit well, but it was not up to the task and fibrated so much that things would fall off the scooter all the time and I had already taken all the bodywork off of it so the things falling off were usually important bits. What a mess.
 
i don't understand so much brokespeed's last post cause of my english... but i have understand the main problem...

so what do you think about this solution??


blocking the subframe on the main frame would be better or worse ???
i think there is a defect in this subframe, cause the engine-support has only 1 lateral attack to the frame...indeed of 2 of the subframe i have posted a few days ago...
 
SaTanaSsO:

My guess is that if you "block" the sub-frame to the main frame it would be worst....more vibrations....subframe is intended to be insulate from the main frame with the rubber blocks and springs it has.
 
Yes, it would vibrate very much. But it would be very stiff. Maybe for some racing this would be good? but I do not know. I think it would also put too much stress on the engine cases as well. Has anyone ever broken the mounting on the cases?
 

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