I have a Eton Viper Mini-50 that dies at full throttle unless the choke/enricher is half way on. Also when riding sometimes I have to let off of the throttle and then push it again to maintain the speed of the engine. I have tried to adjust the jet needle position but not much difference is noted. As of now the stock airbox is off of the unit to aid in working on the carb. Any help and suggestions that could be provided would be greatly appreciated. Thank you

Tom S.
Wells, MN

 

Did you clean the carb? I'd start there.
How old of machine is it?

 

Thank you for the reply. Yes the carb has been cleaned and the e-clip on the needle has been set to the middle notch. There are five notches on the needle. Thinking that maybe the mixture needs to be richened up a bit since that is what the enricher does correct? Also if you try to go to full throttle the machine just bogs down and dies. It is a 2005 E-Ton Viper 50M(mini-50). Engine has been taken off and cleaned. Have not replaced the spark plug as yet.

Thanks
Tom

 

I think a compression test is in order.

 

Besides a compression test what else can be checked?

 

Get a new plug. I missed that. You can try lowering the clip. That'll get more fuel in there.
You can see if the pipe is gummed up. Sometimes there is a screen in the end that also can plug up.
Borrow a comp tester while your getting a plug. Most autozones/etc have them.

 

I am now having a problem with the engine surging up and down and full throttle. What could that be?

Thanks
Tom

 

Needle installed incorrectly (floating), a crank seal, other air leaks

 

I tightened up the intake manifold bolt for the carb. That help to get a nice steady idle. I am still getting a little bit of smoke through the exhaust it is not really white per say but I still cannot hit high throttle without the bog and what seems like the engine knocking.. I am really confused now. Please help.

 

I'd do a compression test.
Did you buy that 3 dollar plug yet?