Suzuki 2 Strokes

As some of you may have read in my trip post:
http://www.motorcycleracer.net/phpBB2/v ... php?t=3019
My 1969 T-500-II made it the first 160 miles with no problems. Then in 100 degree heat and a dirt/gravel uphill section, I lost all power. For the rest of the trip the engine seemed to run well for the first 10-30 miles then it would starting pinging and having trouble with the right cylinder.

Battery read 12.8v when off, and still reads 12.8v. I'll check it again while running, but I do not believe that low battery was the issue.
I am a bit suspect of the plug caps. I replaced the left one on the road, which appeared a tiny bit loose, and will replace the right cap, but this wouldn't explain why it only happens after 10-30 miles.

Timing appeared a bit off and we retimed the bike in a gas station parking lot with a timing gun, after which it was much more responsive than it had been on the entire ride. The 10-30 mile pinging issue persisted. Timing was checked again but was spot on according to the timing gun. I am thinking that this is the highest probable issue, and that the bike MUST be retimed with a dial indicator. This is my first priority.

However, I have recently read some scathing reports about SIMILAR issues to what is happening to my Titan due to KEYSTER Carb kits. Roughly 1000 miles before the trip I rebuilt both my carbs with Keyster kits, so I am extremely concerned by this. The root of the issue seems to be the needles themselves? Evidently, due to the fact that the Keyster kit supplies needles in a different material that the original, it screws up the carb operation? I read a report that one individual had to place the clips on the lowest setting in order to get proper operation.

So, does anyone have any insight into the carb kit issue? Anyone else have issue with the keyster kits, specifically the needles?

It might be a non-issue after I do the dial timing...

If I am not mistaken, the taper is different in the kits and I think the needle + seats are questionable too. The tapered needles were OK on mine ('76 GT500 9,000 miles), but I got Suzuki jets and needle + seats, gaskets. Most certainly change the sparkplug caps. I had a Honda powered pressure washer that after a few months I had to put a non-resistor sparkplug in it to start it. Once it ran for a minute, put the OEM plug back in. It turned out the resistor in the cap was bad, new cap, no more plug changing.

Mr Bond,
Thanks for the response, you're always helpful!

Current situation:
Timing is still correct per timing gun, still need to do the dial setting.

Fuel lines and petcock have been checked/examined/changed and there appears to be no issues with fuel delivery. I am getting some air bubbles in the lines after sitting for a bit which I would expect would be from fuel evaporating from the float bowls. Will keep an eye on it when I get it out for a long run.

Replaced the needles in the carbs (keyster) with my original needles (suzuki) which do appear to have a slightly different taper, different material and different number !?!? Bike is now running very strong on warm-up and revving in the driveway. Hope to get in a nice 100 mile + ride in to check out if the situation is fully resolved.

Will post up if I'm able to get either the ride done or the dial timing setting done.

Cheers!

Not to belittle timing lights, but mine (GT500) ran like crap setting it with a light, tried with a dial, some improvement. I think this maybe a classic case of don't fix what ain't broke. If the the bike is starting good cold or hot and running good at all speeds, etc. LEAVE the points alone. Apparently you have set your timing the most suitable for your engine. Despite being an assembly line made machine, each one seems to have a unique 'personality'. Now if you begin to have a combination charging and ignition problems, there is a company in Holland I think, that makes a drop in replacement stator/ rotor assembly that gives you electronic ignition and a big boost and better control of the charging system. It is expensive, but if you plan on doing a lot of long distance riding, give it a thought, only though if you are have problems that won't go away. Having said all that (too much) if it runs good on the points, use 'em. In the field, you could more easily fix them than a CDI ignition. Since mine came that way, I have a spare in place. If one dies, swap wires and I am running again. I almost forgot, if it still dies when it gets hot, usually this indicates a bad condensor or coil. If both of those check fine when hot then the last place would be the stator. Things to check may also include checking compression when hot and maybe even doing a crankseal leak test.

Cheers for the additional tips.
I neglected to mention that I'm getting great power while running, 13.8-14.2 if I remember correctly from checking the rev range under 5k across the battery.

I have been suspecting the timing because of the pinging, so I'm going to give the long-get-her-hot ride a shot and see if I get pinging or loss of power again before I troubleshoot anything else!

Might be worth checking for any air leaks in the intake system as well

Excellent idea. I recently changed the carb. to air filter boot and noticed a big difference in how it sounded and ran. The tubing going into the boot was not completely sealed around the edges and I had a devil of a time getting them to attach to the carbs. The part is still available and I think it was around $35.00.