Inconsistent performance ride

[Jacobn]

Hey. I have a 66cc bike I built several years ago by a flying horse brand. It was my second engine. When I ride it I’m getting very inconsistent performance. Different speeds. subtle but inconsistent idle. Some of the inconsistencies include dieing after a moment on idle. It has that hp carb with plastic bowl. It’s been cleaned. Good spark wire and plug. Matched my plug by comparing to a autolight small engine plug at Walmart. Basically the same heat range. Gapped to 30. runs well with a ap25 platinum saved from my mustang. All of these plugs have same thread end lengths.
But no matter which it’s pretty inconsistent.
Bike is a hyper cruiser bike

Does anyone have thoughts? Today I tried that rich oil ratio I read for these engines. 25-1 or so. It’s boggy as hell with it and just can’t seem right.

 

[Jacobn]

 

[GW's Motorized]

Id be willing to bet your issue is the HP carb. The HP carb is very difficult to get to run right. Get a JRL bofeng carburetor. I also suggest you get a NGK BR6HS and gap it to 25 thousands.

 

[cloakedvillain]

Id be willing to bet your issue is the HP carb. The HP carb is very difficult to get to run right. Get a JRL bofeng carburetor. I also suggest you get a NGK BR6HS and gap it to 25 thousands.

The stock nt speed carbs work well enough if op still has it. Not great but it works just to get it running.

 

[Jacobn]

It runs well. For my liking it’s just 100% inconsistent.

 

[ImpulseRocket]

It runs well. For my liking it’s just 100% inconsistent.

That is how those HP carbs are. Most people give up on them and either swap out or settle for it having running issues. What most people complain about is either poor idle and low rpm, but great while riding and at wide open, or idles great but the fueling while riding and wide open is never right.

 

[Jacobn]

That could have it pinpointed. May change carb tomorrow

 

[Jacobn]

The flying horse included the hp carb but I have two of the nt stock carbs

 

[Jacobn]

That is how those HP carbs are. Most people give up on them and either swap out or settle for it having running issues. What most people complain about is either poor idle and low rpm, but great while riding and at wide open, or idles great but the fueling while riding and wide open is never right.

Hey folks my flying horse kit from years ago has this device on the exhaust I can’t seem to get it to take a seal lately. I don’t remember what it is.
The kit isn’t available anymore for a hint. Does anyone know what it is? the leak definitely has a negative impact on flow. It pops and spits. Had it off recently. Trying to let it seal with steel epoxy now

 

[Jacobn]

I can tell the nt carb is better.
There is just no controlling the Hp plastic carb this one came with