Startup Jetting After Top-End Redo

If all goes well with assembly I will have an 1135 piston kit and freshly bored cylinder block installed and ready to fire up next week.

I have 115 pilot jets in my RS34's currently, and have been running lean to compensate for burning engine oil.
117.5 pilot jets will put me back in the mid range with the air-jets sizes, whereas the 115 have me just one step away from the richest air jet size available.

Hoping the sync won't be too far off, considering it is set really nice right now for the low-compression pistons and worn rings.

Any relative advice will be appreciated.

If the carbs worked fine before the new top end no rejetting is needed

baldy110 wrote: If the carbs worked fine before the new top end no rejetting is needed

Ok, so no change with the bump in compression, and the increased compression ratio from 8.9:1 to 10.25:1 ? (Plus or minus on those figures btw...)

How long after initial start up and ride(s) will be the best time to sync the carbs? The process for me to get them close should take around ten minutes, with engine running at or just above idle.

:whistle:

You should be able to sync the carbs almost immediately. Be sure to use a fan blowing on the engine.

Yep, no change in jetting. I sync carbs after breakin only because I'm paranoid about overheating a new engine and getting breakin right.

Same kit with NOS 82GPZ cams. BS34 externally vented carbs. Dynojet needles one down from center (raising needles up 1 notch). Smaller stock pilot jet. 132.5 large head mains. Delkevic exhaust w/K&N pods. It'll pull from 1500 thru 7500 rpms. Fantastic go power from 4000 up. Yeah it mite be a little rich at idle, but I don't ride the streets, I'm on the hi-way around here. Consistent 32mpg using 93 octane non-ethanol fuel. Oh, it's got 40k on the lower end, and has had a rod or wrist pin tick for 22k miles. Like that when I got it.

He's running RS34 carbs not BS34 so the jetting your recommending won't work.

The 15 pilots were too lean, so 17.5's were installed.
New spark plugs after 100+ miles with 17.5 pilot and 0.7 air jets, using 93 octane E10 gasoline:



Went through another half-tank of 91 octane (Non-Ethanol) premium, and added 87 E10 to top off.
If she likes it, will be 100% 87 E10 thereafter.

In an effort to fine tune the low-end slightly, I lowered the needles (one slot) to the center clip position, and changed from 0.7 to 0.6 pilot air jets.
This subtle change eliminated deceleration popping, and smoothed out acceleration and the transition between shifts.

Best it's ever been, and I've never been happier with this bike!

Thanks guys...

Forgot about the main jets, which I had progressively leaned down to 115's with the previous oil burner.
Installed 117.5's last night and went for an hour blast around town, and on the highway.

Went back to the 115's, and took the cold forty five minute ride to the Winter storage barn. It runs great.