Removing the airbox from my PPL150 ?

[mrrmutt]

I decided to remove the airbox and all the extra tubing ect. and put on a pod type filter. I had been running with the airbox but no filter in it. I have a 175cc kit on it and a gianelli pipe.

After removing the airbox I started it up in the shop and it sounds good, revs up good, but at WOT it dies. I put in the biggest main jet I have, a 120, but it still dies at WOT at no load. I have ordered new bigger jets. Could it just be fuel starvation because of the increased air flow or did I disconnect something I shouldn't have? What should I do with the line from the valve cover? the extra one one the carb manifold? and is there anything else I should know?

Now would be a really bad time to blow it up again because I want to take it to Amerivespa in June.

[marioG]

jet 120 is like standard for 150s......
130/132/135.....think u need to change idle jet....first try with screw...
ported head?

[mrrmutt]

I had a stock #110 but went up when I put on the new jug. Using the stock head without any special porting.

I looked at it a little more last night and It doesn't really die at WOT, It starts to die then picks back up. If it was gravity fed I would think the fuel tap wasn't keeping up, but with a fuel pump it should keep the bowl full easy.

Hopefully new jets will be here soon. I ordered #122-130.

[mrrmutt]

The bigger jets came in today. I popped in the 130 main and it had the same effect. At WOT the engine would try to die, pick back up, and try to die again, like fuel starvation. I put the stock equipment back all but the airbox (took it off the snorkel) fired it up and it ran as it should. Maybe I'll just mount a foam filter at the end of the snorkel.

Any suggestions?

[mrrmutt]

Is it possable that the aftermarket air filter is more restrictive than the airbox without a filter?
It is this type http://cgi.ebay.com/ebaymotors/Performance-Air-Filter-Scooter-Go-Kart-GY6-150cc-SILVER-/200590336670?pt=Motorcycles_Parts_Accessories&hash=item2eb41da29e

[Punk052]

Comapare the surface area from the original and the new filter pod. I bet the new high flow one is smaller and more restrictive. also the air box and long intake tube hold a greater amount of air and balance out the surges in the intake that a single cylinder engine produces. A foam type filter in the original airbox with holes drilled in the side sounds good and works great.

[marioG]

what carb size?

[mrrmutt]

It's the standard carb, I can't remember at present. I ended up drilling the airbox and not running a filter at all. I know the eventually I'll pay for that but I'll have a lot of fun till then.

Destroying scooters, its what I do.

[sidthesloth]

It's the standard carb, I can't remember at present. I ended up drilling the airbox and not running a filter at all. I know the eventually I'll pay for that but I'll have a lot of fun till then.

Destroying scooters, its what I do.

Apparently so.