Motorcycle Questions? Ask a Mechanic.
Hi and welcome to the site, I’m Louie. Sorry you had to wait awhile but I’ll do my best to help.
Initially, let's try check and review the basics. Proposed preliminary tries (if have not been done):
Appreciate the post back.
On "...removed airbox...cover with hand while cranking. It gets good suction...", did your palm got wet with fuel?
I understand Tim.
Considering that "...Plenty of fuel in carb bowls..." yet palm was dry when covering the carb mouth, then the contents of the bowl are not rising, It would be indicative still of a carb issue.
When the carbs was cleaned, did you all soak the metal parts into carb cleaner solution?
Checked all the jets? ...ensure all small holes are not clogged? ...used carb cleaning brush similar to the product shown HERE?
Please click HERE.
Bear with me and re-check/re-clean # 12, the pilot jet and where it is screwed into the carb body.
Additionally, adjust/turn # 13 to 1¾ out from fully seated.
...and would look forward to the update when able.
IF #12 is surely clean, then it would be the very small hole of the carb body itself that may be clogged.
Please consider (re-) soaking all the metal parts overnight or even longer.
I understand and when able...
Either a small screw (least likely) or it is force-fit (most likely). Consider soaking with this fuel inlet tube on top and the cleaning fluid level just enough to have the metal parts submerged.
With these carbs full cleaned, install the air box + filter and ensure correct/snug fit with no air leak.
I would beg to disagree; this model/type would tend to allow more air entry and results to a very lean mix (spark plug whitish) hence would call for a rejetting to compensate.
If running stock jets/carbs, then please use stock air box + filter.
Or consider changing the jets.
Or a workaround if not for test purposes, slip an extra outer layer of generic air filter foam over the pod filter.
While test tuning, I used old woolen socks 1 over the other.
Also, bear with me for likely delays as I would be mobile later playing husband and father.
Still a no even when starting considering lower RPM during cranking thus lower vacuum = lower suction to gas intake hence with pod type air filter, the vacuum is further lessened = poorer starting suction.
Appreciate your patience/understanding.
For test purposes and as posted above, add an extra outer layer of generic air filter foam over the original air filter inside the airbox. It may even take 2 or 3 layers.
The objective is to reduce volume of air intake to make the mix just slightly rich.
Then test start. If still a no-go, attempt to re-start working the throttle as if trying to flood the engine. Then remove the spark plugs and see if these got wet with fuel.
Yes please when conveniently able.
Sorry but I would beg to differ based on the earlier description of "...cover with hand while cranking. It gets good suction..."
Rather than an engine/vacuum issue, it would more point back to the carbs.
Please click HERE. There are two (2) pin holes on the carb yellow tunnel; blue and red (air & fuel respectively). These are responsible for the idling and start up air/fuel mix to be fed to the engine.
When #s 12 & 13 were removed for cleaning, did passing a thin stiff wire where 12 & 13 were resulted to the end of the cleaning wire to appear through the yellow tunnel?
These parts are necessary for replacing below parts IF and only IF:
And as posted before.....Checked all the jets? ...ensure all small holes are not clogged? ...used carb cleaning brush similar to the product shown HERE?
passing a thin stiff wire where 12 & 13 ... resulted to the end of the cleaning wire to appear through the yellow tunnel
Great! Good to hear that the issue has been resolved, congratulations.
Good luck and thank you too for the opportunity to share the information.