Bog of Idle when choked won't run without choke

[gooch]

Seems a bit extreme becuse it ended up that way. Its been with my buddy all summer. He works a lot of hours but has been tinkering on it as he can and weve found out that the timing was way off. We could never get the jetting right, it was acting starved on fuel but would backfire so we checked ignition timing and it needs to be set so far off normal that we now think a cam jumped time. Im at my wits end with this (what started out) cheap build project.

Good luck man. Ill post back if/when its running.

 

[theimbalance]

Well, I went ahead and ordered a bunch of bigger pilot jets, I believe I ordered a 35, 45, and 55. They will be in this week, I'll report back with my findings!

 

[5twins]

45 and 55 pilots will be way, way too big. Even the 35 may be a bit much. Sort your mains and midrange first, then do the pilots. Their size is influenced and can be determined by those other settings. 27.5 is the stock pilot size in the '78-'79 carb set. Most go one up to a #30 but sometimes two up is needed. That would be a 32.5, not a 35.

 

[gooch]

So the cams on my bike are good, they're in time and the chain looks good. Ignition timing is as close as it can be without it running right, which it still isn't.

Still acts as if it's starving for fuel and I'm not sure why. It was suggested, like so many times before, that a circuit in the bowl is plugged. I haven't done it recently, but whenever I blew carb bleaner through the holes it flowed as good as I would imagine it should.

I've tried running it before without the pod filters to make sure they weren't interferring with anything.

I'm hoping to get to work on it tonight, between the kids functions and my after work functions I haven't had much time to play with it.

 

[theimbalance]

So to report back, I've had the 45s in the bike for quite a few weeks now, and it starts, idles, and drives the best it ever has. Now I haven't checked my plugs religiously, I'm just happy that the thing starts after a few light kicks and idles. I will note that with this rich of a pilot jet, it does not need the choke to start.

I had an ah-ha moment after going through many steps over and over. I filled the gas tank, and no longer had the bogging and not running without choke issue. So, I have narrowed it down to either a clogged gas cap vent or leaky vacuum petcocks.

 

[gooch]

That's great.

I've made no progress. My petcocks are not vaccuumed, my cam timing is good, my ignition timing is close, my jets are where they should be, and my carb was cleaned about 10 times and soaked in an acid bath at a shop with new gaskets.

I think I'm honestly ready to sell it.

 

[Chito]

Forgive me if I missed someone mentioning this, but have you checked the carb boots for leaks? I run pretty close to a stock set up, so I don't have the weight of the carbs fully supported by the boots, but mine were still bad from sitting a long time before I got it.

 

[gooch]

they seem tight, how would I double check aside from a visual inspection?

What I need is to make buddies with someone else that has an xs so that I can borrow parts like carbs and boots so I can see if they're the issue.

 

[weekendrider]

Do you have a small propane torch?
You can use it to find vaccum leaks. Crack the valve open and run the tip around the carb boots.
Some used to use WD40 and that worked back when they used propane as the propellent. Not so now.
Starting fluid and carb cleaner are hard on rubber. But you can use those.

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[gooch]

Dead thread revival.

Update.

After being filed with a divorce and holding onto a problem bike for the last year(s) I decided to take it into a shop that specialized in the Jap bikes. I wasn't figuring it out but wanted something done.

They started with the carbs and intake boots that were leaking a bit of air (which I found with the spritz of ether while it ran)

After that they were getting off temp readings at the exhaust (weren't anywhere near each other) so they checked compression. I had bad rings all along.

Sooo, after a lengthy stay at the shop near Kalamazoo, it's got new rings and pistons and a cleaned up cylindesr, (didn't need a bore)

Finally got to ride it into work today so that I can read the plugs and tune the jetting. She's popping pretty bad on de-cel and wants to race on choke. I've got a nice sandwich bag of Jets from playing with it for the last several years so I'm hoping I'll get it squared away soon.