Anyone know about 2stroke bikes?

[badchild]

I got a cagiva mito and at 80mph it just seems to splutter, theres fookin good lift out of every other gear but it seems to just choke itself at 80, im thinking maybe its not fully derestricted? the exhaust has been derestricted does anybody know if there is anything else restricting them?

 

Also i fitted new back pads and the brakes wont bleed right, can anyone explain?

 

Cheers Ryan

[Trevmk3]

Hi Ryan, not sure about the problems myself but if you try a forum like http://www.visordown.com/ im sure that there will be alot of knowledge of 2 strokes on there

 

hope this helps you

[GT_Jim]

ive had a bit experience with carts which have bike 2 strokes by the sounds of it the top end burn isnt right which is down to jetting or the height of the needle

[Mr Sam]

has it got a fuel adjuster on the side of the carb

rev it like hell and adjust that untill the revs are at best

 

i tuned up an ancient yamaha scooter once had a race with some shitty scooter and trounched him.....ill further add had no air in the front tyre what so ever

[Cookie]

Sometimes they are restricted via the reed valves, might be worth checking , failing that it may not be set up right or even thats all its got, if it's a 125 80mph is good going

[Jimbob-Squarepants ©]

What exhaust pipe is fitted? Is it an aftermarket performance pipe? The Mito should be good for at least 90mph, and about 105mph slightly tuned.

 

Try taking out the reed valve and holding it up to the light (while looking through it), if you see daylight through the petals (flaps), you will need a replacement. The reed valve allows the fuel/air mixture to be compressed in the crankcase so it can be sent through the transfer port to be compressed again by the piston. If the reed isn't closing as it should, the fuel/air mix wont be making it's way to the top of the bore... either the whole lot, or not enough.

 

The same can also be said for the crankshaft seals, if these aren't sealing properly, there will be an air leak into the crankcase.

 

I would also whack the carb of and give it a good clean out with some carb cleaner to make sure you have so shite in there or blocked jets. Once clean, set the mixture screw about 1 - 1 1/12 turns out. This will get it running. Once running, let the engine get up to running temp and adjust the mixture screw untill the engine is running at it's fastest and smoothest idle. Then adjust the idle screw to set the engine idle.

 

Oh, one more thing, 2 strokes love a spark plug. Get yourself a replacment as if it is running to oily, it will burn the plug out. Obviously, if you are at speed with the engine on load, the plug is under alot of pressure, so if the the spark is weak, or the plug is breaking down, it could well be the cause of your problems.

 

Hope this helps, and good luck!

[Mick The Mig]

When my lads had resricted bikes we found the most common way the makers would use to cut performance was to fit a longer throttle slide so that at full throttle the carb' bore wasn't fully open. drop off carb, open throttle if you can't see a clear circle opening then the slide is to long.

[Luke_hpe2.1]

change your reeds to v force reeds or carbon reeds make so much difference. Make sure your new reeds arent too thick they need to be nice and flexible. With the v force reeds you can also adjust the tension. Another trick is to port it a bit. Also another trick we did when we were racing if it has 2 rings snap one off and run one... less drag You could also advance the timing up a little. Open the inside of carb and inlet up. All you need is a file or dremel. Also as commented get a good plug like an iridium... Also check your plug colour you could lean her off a bit with a smaller mainjet. Need any more info just ask. Quite familiar with them as i used to race polinis, motocross bikes and 2 stroke karts air and watercooled.

 

Luke