PHBG + MLM Hobbit Pipe

I've been having issues ever since I put the pipe on. So here we go:

My set up before:

'78 Hobbit PA50II

DR kit

Boyesen dual stage reeds


Stock Carb

The bike was running amazingly well, and I was super stoked to put the new pipe on and rip... quietly for once. But that's not what I got. With the new pipe on, the ped seemed to be 4-stroking on the bottom. But if I peddled enough to break the threshold and get into the pipe, there it was... zoom. I then pulled the old school original air filter and it helped the off-the line a lot. Seemed like it was just choking for air.

A few days later I ordered the Malossi 21mm PHBG Carb kit. It came in last night, (I looked at the wiki and chose a 48 idle jet and a 90 main... it came with a 60 starter jet and a w7 needle which I put at the 2nd notch from the top) and after finally getting it into the subframe, I thought the thing would rip, but no. It idles perfectly and revs well at ~1/4 throttle. But then at 1/2 throttle the thing just bogs out, to the point of killing the engine if I don't let up. Again though, if I get it going at 1/4 throttle and then pedal to get the speed up, I can get past that 1/2 throttle bog to WOT and once the power band hits, torque city!!

So, new setup:

DR Kit

21mm PHBG

MLM peoples pipe

Boyesen 0.4 single stage reeds

What is the deal? Needle too high? Too much gas? Not enough air flow because of the side bleed? I have not pulled the weird 3 hole air intake thingy, and the original filter is still removed and the new additional Malossi filter is in place. I also have not opened up the exhaust port of the DR cylinder yet, which is something I might try tonight.

In Denver btw, and want to get this thing ripping for tomorrow's rally. Any other ideas? Please help. Thanks

Re: PHBG + MLM Hobbit Pipe

jets jets jets. try them all. sounds like a lean bog in the middle.

Re: PHBG + MLM Hobbit Pipe

Really??? Doesn't seem like a lean bog... seems like a rich bog from my limited experience. I've got all sorts a jets... but not many people go lower than 90 with this setup. I am at altitude, but usually the Hobbit can handle being a little rich no problem.

Any thoughts on whether matching the exhaust port of the kit to the pipe might help or not?

I may just bolt the proma back on as a trial to see if it's the carb or the pipe. and go from there.

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