Rough start

Well damn! Yea I know I know... keep it coming....:p let off on the poor gal. :notworthy: I get it. :doh:

Yes. There was plenty of gas and the clip is on the halfway mark. Yet the guide also calls for removal of the air jet. And yes tightening that air screw 3/4.
 
tightening that air screw

jasidok - not to split hairs, I wouldn't use the word "tightening" with a carb adjustment. You want to go very gently on these little brass adjustment screws - and make changes slowly and methodically.

Stick at it - you'll get there.

Pete
 
In the guide, like the very first part, he’s saying to get any “step up” with the dremel. What in the gosh darn tarnation is a “step-up”!? I’ve looked and I don’t get it.
 
In the guide, like the very first part, he’s saying to get any “step up” with the dremel. What in the gosh darn tarnation is a “step-up”!? I’ve looked and I don’t get it.
This what you're talking about?
"There's a bit more involved than simply bolting up the mounts and popping the carbs on. As a first step, fit the carbs to the mounts on the bench, remove the slides, and check for any up-steps where the spigot meets the mount. If you find a step, smooth it away by working the mount with a dremel or similar tool. Then hang the mounts and check for any upsteps where the mounts meet the ports after you've positioned the mounts for best fit. Work the ports slightly to match."


It basically means to adjust (grind) the carb mount if it's smaller in diameter than the carb. Might be something to revisit, but unlikely to cause 'em not to work.
Keep readin' ;)
 
I was curious if he had fouled the plugs out getting it to cough on choke. Given everything else you've done and verified so far I'd be reaching for a can of brake cleaner to make sure it will pop over like that. Verify that it is a fuel problem.
 
that engine is not even trying in the video. There has to be something fundamentaly wrong because it should start within 2-3 turns of the crank every time.
At the very least the engine should cough or backfire .

Either there is no spark at the plugs or there is no fuel on the plugs or you have the timing so far out that you have no compression at TDC or the plugs are getting a spark at the wrong time but even then you should get some firing

With all that cranking there should be fuel everywhere it should be soaking wet on the plugs and stink the place out.

Like nashGTI says Try squirting Easy start or similar accelerant straight into the inlets and then use the starter. it should start up instantly and run for a few seconds at least.
 
.That jetting is Sudco's setup for the XS650. The PJ is much leaner than the baseline I offered in the Carb Guide because Sudco uses a rich 2.0 slide.
 
K. I’ve been working my way up the ladder here. I’m at 17.5 Pj which is the only fatter pj I have. I’ve really been taking my time here and making sure everything is on point. I’ve gone a quarter turn at a time. Starting at 3/4 turns out. I have started getting good sound. She wants to start. It’s a lot of backfiring though. I’ll upload a video of me not destroying the starter motor. :thumbsup: Still not holding it down or turning over. It’s definitely getting warm. I have the choke on. I’ve alternated on and off. Give me a few and I’ll take a video. Thanks for all the help... even though I might look like an idiot sometimes. :cheers:
 
Kinda late in the game to be asking.... but did the bike run before you replaced the carbs?
 
I’m sorry. Yea it did. But it was so rich it filled the whole garage with smoke a couple times. And I went through like 3 sets of plugs. It was those “keihin” pwk33 s that I literally gave my all into. They just ran too rich man. So I left it alone for a week while I waited for these bad boys.
 

Pj: 120
Mj: 175
Air jet: removed
Air screw : 0 turns
Needle clip 3 / middle
Choke off in this video. But I’ve switched on and off.

I’ve checked the valves. They’re good and weren’t off. The cam chain tensioner is good.

Any ideas on maybe adjusting the timing?
 
jazidok it would be really helpful if you put your bikes model year and ignition , carb and exhaust details in your signature it will save us having to spend ages searching through dozens of your previous posts to remind ourselves us of this information every time. ;)
please remind us what type of ignition and advance you have as I can't be assed to go searching for it again.

In your video it sounds to me like you have the timing set too advanced . It sounds like the engine is firing in the inlets due to the inlet valves not being fully seated .
Did you try using an accelerant like Easy start as suggested ?
 
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Use a timing light, hint it's easy to use a timing light with the electric start if you remove the sparkplugs. Admission; with madness I advanced til it began kicking back when starting then retarded til the kick back stopped.
 
jazidok it would be really helpful if you put your bikes model year and ignition , carb and exhaust details in your signature it will save us having to spend ages searching through dozens of your previous posts to remind ourselves us of this information every time. ;)
please remind us what type of ignition and advance you have as I can't be assed to go searching for it again.

In your video it sounds to me like you have the timing set too advanced . It sounds like the engine is firing in the inlets due to the inlet valves not being fully seated .
Did you try using an accelerant like Easy start as suggested ?

Ok! That sounds good. It is firing in the carbs. I used a bunch of starter fluid a few different times. It mainly just had a loud backfire and sometimes flames shot out the carb. But it still never actually ran. I can hear it trying through the exhaust.

Use a timing light, hint it's easy to use a timing light with the electric start if you remove the sparkplugs. Admission; with madness I advanced til it began kicking back when starting then retarded til the kick back stopped.

Ok. I can use the timing light even though it’s not started? Is there another option for adjusting the timing or something of that nature that I’m overlooking? I’m asking in addition to adjusting the timing at the Pamco. I’m just checking. I really feel that my issue lies in the timing or something not working correctly in that arena. Because I have gas. I have spark.

I’ll let you know the results in a few. Thanks again!

1978E Special XS650 2-1 exhaust
Electric Ignition - Pamco w/ mechanical advancer; Dyno 3ohm dual tower ignition Hey coil
VM34 Mikuni Carbs currently—
PJ: 120; MJ: 175; Air Jet: removed; 6F9 Needle; 159 P-6 Nedle Jet
 
Ok! That sounds good. It is firing in the carbs. I used a bunch of starter fluid a few different times. It mainly just had a loud backfire and sometimes flames shot out the carb. But it still never actually ran. I can hear it trying through the exhaust.
That's a great indication that your primary problem at least isn't the carburetors. Were it simply a fuel issue the starting fluid would've got it to run for a moment or two.

Timing light will work on the coil firing, and the coil fires whenever the engine turns over. Like Gary suggested, take the plugs out, wedge the throttle open and just spin it over on the starter. You should get a timing like pulse just like you would if the engine was running.
 
thats a really helpful post jasidok thanks for the specs.

i'd forgotten that you still have mechanical advance . That is where I would start looking .

i'd thoroughly recommend that you add Pete's electronic advance to the pamco and do away with the mechanical advance so that your ignition and advance is fully electronic .best investment you could make I reckon. Push button starting and perfect advance curve from idle to WOT top speed . Once fitted you can forget it.

That's a great indication that your primary problem at least isn't the carburetors. Were it simply a fuel issue the starting fluid would've got it to run for a moment or two.

.

this is why Nash and I suggested trying a starting fluid because they can be used as a diagnostic tool . There is always a reason behind suggestions even if not immediately apparent.;)
 
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