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Trying to get my 1983 R65 going, and cannot get it to cold start without significant crank time (about 1.5 batteries worth). If I can get it to start, it will subsequently start fine once warm (pretty common, as I've read).

At best, the bike will "catch" a little for every 2-3 seconds of crank. If I slightly blip the throttle and release, it seems to encourage this "catch" but still won't start. Enrichers "on" make it so it doesn't "catch" at all.

What I've checked/tried:

• Valve clearances: .006 Intake, .008-.010 Exhaust

• Rebuilt carburetor w/ o-rings, diaphragm, gaskets

• Clean carburetors (including enrichener jet in the bowl)

• Confirm float levels: checked out against Snowbums suggestions, fuel cuts once float arm is parallel

• Confirm spark (blue/white)

• Advance timing slightly

• Verified throttle cable "slack"

• Confirmed butterflies are properly oriented

• New intake boots

• Test with different charged battery

• Move jet needle c-clip to position 2 from position 3 (to lean out)

The only visible indicator of an issue is that my intake boots are wet on the carb-side. I do have new float needles on the way, but, I'd think I would see overflow if this was the issue.

Any suggestions are appreciated. Thanks!

Welcome! Have you confirmed that when you turn the handlebar choke (aka enrichener) lever on, that the levers on the sides of the carbs actually move to their proper position? Sometimes working on the carbs and dealing with the enricheners they can be reversed from left to right and also the gaskets on the covers to the enrichener don't actually seal.

Kurt

Thanks, Kurt!

The handlebar enrichener lever has been relocated to pulls nears the carbs, and they are moving from fully off to fully on.

Them being reversed from left to right, however, isn't impossible. I may go swap them around and see what results!

Have you checked the compression?

Kurt, the enricheners were on the correct sides.

gspd, just went out and checked. Carb off, plug out, and cycled 8-10 times. 135psi on left, 140psi on right.

Probably should have first asked...is this bike new to you or has it been running before the carb overhaul?

Sounds like you replaced the o-rings on the carb butterflies. They go back on in a specific orientation. I forget the specifics, but a "dot" on the surface is supposed to be in a certain spot.

Kurt

It has been running before. I've actually done carbs gaskets and o-rings twice - once about a year ago (as part of a larger bike refresh), and then again just last week to try and address this cold start issue. I don't remember having issues after the first time, but then, my memory is foggy with this bike.

I was unaware of the required orientation - we're referring to the single o-ring on the butterfly shaft? This could make enough of a difference to prevent start-up?

rounders wrote: ↑Fri Aug 16, 2024 5:37 pm The only visible indicator of an issue is that my intake boots are wet on the carb-side.

That implies you're getting fuel.
Are the slides lifting when you crank the engine over? (you need air too)
(I'm assuming you lined up the diaphragm notches when you replaced them.)

rounders wrote: ↑Fri Aug 16, 2024 5:37 pm Confirm spark (blue/white)

.... hmmmm...
Do you have (or can you borrow) another ignition coil to try?
Should be a FAT blue spark at the plugs.

rounders wrote: ↑Fri Aug 16, 2024 7:16 pm I was unaware of the required orientation - we're referring to the single o-ring on the butterfly shaft? This could make enough of a difference to prevent start-up?

The butterfly can easily be installed wrong, it has tapered edges and must be positioned precisely in the carb bore before tightening (and peening) the screws that hold it to the shaft.
BUT...This only matters at idle and at very small throttle openings.
That said, the bike should start and run, albeit poorly, even if they are installed ass-backwards.

gspd wrote: ↑Fri Aug 16, 2024 7:44 pm

rounders wrote: ↑Fri Aug 16, 2024 5:37 pm The only visible indicator of an issue is that my intake boots are wet on the carb-side.

That implies you're getting fuel.
Are the slides lifting when you crank the engine over? (you need air too)
(I'm assuming you lined up the diaphragm notches when you replaced them.)

Yep - I did indeed line up the diaphragm notches, top and bottom.

gspd wrote: ↑Fri Aug 16, 2024 7:44 pm

rounders wrote: ↑Fri Aug 16, 2024 5:37 pm Confirm spark (blue/white)

.... hmmmm...
Do you have (or can you borrow) another ignition coil to try?
Should be a FAT blue spark at the plugs.

I see. I'm still running the OEM crack-coil - I just checked, and it is indeed cracked. I figured the bikes ability to run without issue once started meant the coil might alright, but maybe I'm mistaken.

To your butterfly comment, they are installed correctly.