Hey hows, it going my first post I tried doing a search but kept coming up empty. I got my jetting set to the point there is zero bog when you snap the throttle but the plug still looks sooty as heck. It started out as a Tillotson 212r so 196r head 26lb springs, billet rod, .265 cam. and the nibbi carb. Current jetting is a 50 pilot and a 130 main. It eat's it but figured I'm still running rich and maybe one of you guys could point me in the right direction thanks in advance.
Anyone jet a 24mm nibbi on a predator 212 or Tillotson 212r?
- Thread starter ephenj93
- Start date
130 is WAY to rich. Im running a 108 main. Tillotson stage2. Hot 265, ARC rod and fly with exhaust header and pipe. 112 starts to get rich. I have dyno papers for my predator 212 identical 8nternals. 110 starts to go too rich. Makes 14.51hp at 5k. Everyone in these forum always calling for 130 mains but for these engines thats way too much. Thats my input. Lil late to party lol
How about humidity? I don't have a clone engine, but a 5hp flathead with VM22 and extended manifold runner. Runs great in nice weather with #105 jet but if humidity rises to near 70 or 80% it's like the gas suddenly refuses to mix with the heavier air. But swap in a #115 jet and it'll growl back to life - if still a bit reluctantly.
I have watched a few videos and can agree with this. I started with 130, was always rich. Thought it was me being new to building and just let my engine sit due to frustration of rejetting not getting me anywhere. I have a Tilly with everything you mentioned with 26lb springs and a ported head - I dropped to the 108 and it sounds wonderful now. I also messed up though and bought a flanged type but fixed it with an adapter + RTV - wouldnt of ever went that low if I hadnt seen your post. Thank you.
Glad I could help! I became a pro at jetting the 24mm Nibbi flanged on my tilly 212 stage 2 over last couple weeks because this. I could not get rid of this damn stumble... after weeks of messing around... I found I had pinched the coil wire in the gas tank when I changed out fuel line. I could'nt believe it! lmao...felt so dumb. I have now jumped up to a 115 today but have not had a good chance to test it. I ported out the head some so it was to help with the better flow. the 108 seemed a lil lean so went to 110. Trying the 115 to see if it'll handle it... the cops and the one old lady put a damper on that for today. Her husband rides a big old bike to but must not be a real biker...shame! Any how just glad my tips helped somone out...frustrating tuning a carb. Happy riding my friend!
