All seems good, but not starting...

[Maxim-umm]

Hello again. Update of progress.

Re-shimmed the valves, now they're all within spec. Starts easily, idles rough at first but smooths out as warms up. Still stutters and backfires when throttle is applied. I can get it to rev if I hold the throttle open, but it fights the whole time. Sputters, pop, spit, backfire out carbs (slight), but REALLY backfires out exhaust. I'm talkin gunfire loud. Friend told me to mess with timing, dad tells me can't be timing, probably something electrical, another friend says exhaust could be creating back pressure. I'm thinking I don't know where to start. Timing is spot on, float levels appear good (wet check), can't find any leaks anywhere. Can't seem to get a good plug reading. Starts rich, adjust, then lean, adjust even less, good. Ride, check plugs, rich again. Also, to ride I have to short shift badly. My tach cable broke so I can't give rpms. Here's where I'm shifting:
1st -->2nd = 10-13mph
2nd -->3rd = 20-24mph
3rd -->4th = 30-33mph
4th -->5th = 40-47mph

So here we go. If anyone can throw a guy a bone I'd appreciate it. This has been a most fantastic project and would love to figure this running problem out.

PS - lhaolpa - did not check the spark yet. Off to the parts store now to find the spark checker and give some time to see what ideas anyone has. Will keep you informed.

 

[chris]

Is the inside of the tank rusty? If so, that rust dust will pass right through the petcock filter and seem to always cram itself into the jets causing fuel starvation at different throttle positions depending on which jet is plugged. Hope this helps.

 

[Maxim-umm]

chris - sorry, I forgot to mention, tank was super-cleaned and lined with red-cote. This also happens with my test tank. Both have in-line fuel filters attached.

 

[chris]

I may just be talking out of my ass here but have you tried running the bike with the gas cap open. Not sure the possibility of both tanks having faulty gas cap vents but it sure would be a simple fix.

 

[Maxim-umm]

Sounds like a plan. I'll try that tomorrow morning before I head to work. Thanks for the advice. I'll take any other suggestions anyone may have as well.

 

[lhaolpa]

From experience,make sure the filter you use is for gravity feed,as some require too much pressure,and when a little dirty,will easily clog. lha

 

[lhaolpa]

It may take a little more cleaning on the carbs,and rodding out or replacing the jets,or at least taking them out and poking around with a torch cleaner.If you don't have a tip cleaner,get one,you'll need one.A good one has many sizes and you can choose one that is a bit smaller,so there is no risk of getting it stuck or reaming out a passage or jet.Boiling out is the old method of cleaning,and you'd be surprised how much gunk will be seen in the water after a "clean" carb sits in near boiling temps overnight.I have an old slow cooker,the big one,and I put dish soap like Dawn,and set on high for a few hours,then low overnight.I have left one or two in two or three days,and after cooling in a little water,I blasted the carbs with the hose.I've added a water pik to my arsenal against filth,and will soon test it on a carb,to blast through the passages.I bought it at a thrift store,looking for old T-shirts for working on my bikes,they get dirty really quick,and my wife will not wash them if they are too badly greased up. lha

 

[Maxim-umm]

lhaolpa - didn't even think of gravity feed or not for filters. I'll check it out and make sure I have the appropriate one. I will hit the carbs again for another cleaning the next cold, rainy day....which will be soon since I'm in Seattle I will continue to poke around until then. Thanks.

 

[Maxim-umm]

Well, open gas cap didn't change anything. I'll tear into the carbs next and see what treats I can find.

 

[Maxim-umm]

Helloooooooo world.....
Well, I'm back and I'm RIDING!!!! After weeks/months of frustration, agony, heartache, and my patience wearing very, very thin, I have finally figured out my problem After removing and super, duper, thoroughly cleaning the carbs to no avail, it dawned on my I never checked the pick-up coils. That was the only thing left that I could think of I hadn't gone through. So I pulled the cover off and took a look. Seemed ok, except a few very small metal shavings stuck to the magnets. Didn't think too much of it and cleaned all the magnets. Buttoned her back up and decided to see if she ran any better. Right off the bat she starts up. I let her warm for a couple minutes then rev to see if there's any improvement...beautiful!! It's like a symphony. Now I need to star body work and make her look pretty. Thank you so very much for all the patience and time you all have put into helping me figure out these problems. I'll be back again and again to check up on other threads and updates and once I start cutting away I'll try to start a build thread.

 

[HoughMade]

Sounds good! Who would have thunk it? I'll stick with my points and condenser.