Manco 90 dies warm
 

I have been doing a lot of reading about this thing. First thing I learned is that this engine (Her Chee/Adly) is used in multiple platforms. Second that the same problems can be found on hundreds of threads on many forums. Third that very few people report back to the thread when they found the problem. :cool: So I picked this thing up for too much money :crazy: but now I have to press forward. Symptoms: 1) bogs at half throttle and above; 2) Dies when warm and won't restart until cool. These issues may or may not be related. When I got the quad I pulled the tank and flushed it, new fuel lines, and cleaned petcock. Put on new carb, and checked intake manifold for cracks. New battery of course and new ignition switch. It had sat for a few years with the PO not being able to make it run. So after installing these parts it fired right up. A little adjusting of the carb to get a idle (no air breather yet) and it responds to part throttle by trying to do a wheelie with me on it. Just as it engages the cvt it also starts bogging (no breather?) and you can't really go. If I hold my hand over carb I can ride around the yard. But after 5-10 minutes it dies and won't restart until it cools. Ideas?

Lets hope I am wrong, but the symptoms are a bike running awful lean, which causes overheating and seizure. A new carb is not, unless bought genuine from the bike maker, going to be set for your bike. So may have the wrong jets or gum/dirt in it from the manufacture or storage.

Thanks, the carb is a $20 ebay special that was sealed in a bag and looked fresh from china. On the heating and seizing, wouldn't it be hard to crank when hot (as in slow turning over) if the piston is seizing up? This spins over as fast as usual? I ordered a factory air box from Taiwan so I can get the carb adjusted correctly and then diagnose from there.

Okay little update. I Cleaned the the stator and adjusted the carb some more (rigged an airfilter) and it will run as long as I want it to. Let it run 1/2 hour or so. Still have the lean mis-fire at 3/4 throttle and above. I can cover the breather with my hand and alleviate it a little. So like most people this still just seems to be a lean condition. Going to clean the "new" carb and wait for the factory filter setup. Then start jetting to get the fuel rate right. I have not checked compression because it fires right up. I have sprayed carb cleaner everywhere while running looking for a vacuum leak. Any other suggestions?

Another update. I got the factory airbox in the mail today and low and behold she is running all over the yard! :cool: But now it won't idle after all that work getting it to idle without an air filter. :lmao: So now just need to get it dialed in now that it has the proper vacuum drawing fuel.

Good to hear.. Lots of these machines will not run properly without some sort of air restriction like the air filter..

Another issue I am unsure of is the cvt engagement. It seems to take a lot of throttle to get it moving. What rpm should this thing begin to move at?