Pit Pro 150 with Mikuni Carb - Runing rough

[Spider003]

Trying to sort out carby settings for my Pit Pro 150XR.

Runs and Idles fine, quite good off the line and down low but coughs and runs like a pig heading towards top end (approx 2/3-3/4 throttle).

150 Lifan Engine with 26mm Mikuni Carb

Currently set up as:
Pilot Jet - 17.5
Main Jet - 100
Clip Position - Second to top. If I move clip either up or down seems to make it worse; as does increasing/decreasing the main jet!

Any assistance greatly appreciated. Must be someone else running the same set-up (Pit Pro 150 with 26mm Mikuni Carb)..........

Location - Regional SA (approx. Sea Level)

Cheers

 

[aussie_140]

I'm having the same problem, I've got the same bike and same carby, backfires a **** load

 

[Deacon fmxer]

I had trouble tuning my old fakuni, I ended up swapping it or a oko found that a breeze to tune, after I got the hang of it, plus there heaps of info of them on here. Best bet is to hit up Sean01 that guy knows a lot about minis.

Goodluck.

 

[Spider003]

Thanks for the replies. Good to see someone shares my pain!

It's actually quite a good bike (especially for the $) I just cant get the set-up right to get the most out of it.

I think I need to look at getting a different carby etc.

Any other advice would be great (either same bike and carby or even same bike and different carby set up - including jet sizes etc).

Cheers

 

[aussie_140]

how is it running rough? like backfiring?

 

[Spider003]

Theres only a bit of backfiring etc - But its more lack or loss of power towards the top end. When you get past about 2/3 or 3/4 throttle the power just dies right off (coughs and splutters).

I have tried different main jets - to me, it seems like 95 too little and 105 too much (that's why I am at 100). The 100 is what was in the bike when I bought it new (its basically a brand new bike, its only done a few hours).

Clip is on 2nd highest clip (again, either higher or lower seems to make it worse)

The only thing left is the jet needle! Apart from that, I'm back where I started!

Am I missing anything?

Cheers

 

[aussie_140]

pitpro have stuffed up there! mine has no bottom end power but heaps of top end, sucks coming out of berms! cant really help you to much, but good luck. if i find anything that works for me ill tell ya.

 

[motorman]

Theres only a bit of backfiring etc - But its more lack or loss of power towards the top end. When you get past about 2/3 or 3/4 throttle the power just dies right off (coughs and splutters).

I have tried different main jets - to me, it seems like 95 too little and 105 too much (that's why I am at 100). The 100 is what was in the bike when I bought it new (its basically a brand new bike, its only done a few hours).

Clip is on 2nd highest clip (again, either higher or lower seems to make it worse)

The only thing left is the jet needle! Apart from that, I'm back where I started!

Am I missing anything?

Cheers

Have you checked your timing mate and made sure it's spot on?

 

[Clunk]

My 30mm Fakuni on my pit pro 150 is going in the bin, I rebuilt and cleaned it several times and tried every adjustment but it just didnt want to 'play the game' even though it was fine for the first 18 months before the bike started playing up.
I'd suggest if its not running right just get it sorted before a big session.
Might be an obvious thing to do but i decided to just keep riding even though mine was running rich and by the end of the day compression had almost disappeared.
I found this morning after pulling the head and barrel off.... 1 burnt exhaust valve and a pretty glazed bore.
So now OKO flatslide on way as well as new head, barrel and piston kit.

I was running 100 main and 20 pilot jets clip on the bottom.

Check the valve clearances are .003 inlet and .004 exhaust.When i did my valve valve clearance check the inlet had none.

Without trying to scare you my bike was popping flames out the exhaust and had no top end before i pulled it down and found the burnt valve.

 

[Spider003]

Thanks for all your feedback guys.

Yeah, Timing is OK.

Can't believe I didn't even think of the valve clearances, I have even just done them on one of my kids bikes! Like they say, it's the obvious stuff you often forget. I've actually just assumed given its almost new they would be OK!

It seems to make a bit of sense given the bike is not too far away, so hopefully that's the answer. I'll give it a shot.

I might get a different carb anyway to try, just to cure my curiosity as to whether it will make a difference!

The bloke from Adelaide who has said his 150 has poor low-down power, what are your jet sizes and clip position?

Cheers,