Topic: 1971 suzuki titan 500twin 2 stroke tuning problems need some answers

[micron_52]

so the bike has been completely rebuilt and idles great but after a while its starts putting to much oil (oil injected) into the motor and some how it starts to make one of the carb slides stick, making the throttle stick. we have gone through the carbs they are in great shape, we just dont know how to turn the oil down i guess you would say . the only way i know how to adjust it is by the barrel adjuster from the throttle cable going to the oil pump. need some info maybe if you know any websites that have some info.
thanks   

[RRRToolSolutions]

Ok, there is an easy fix -here is how you adjust your oil pump properly.

See the diagram below and you'll notice there are two marks. One on the arm that your throttle cable attaches and one on the oil pump. You simply want those to line-up at with the bike at rest, idle, turned-off and hand away from the throttle grip (throttle closed) . The setting is controlled by the threaded cable adjuster at the pump. That should take care of it.

The oil pumps are absoluely bullet proof. The setting is designed to give you about 100:1 at idle and up to 30:1 at full throttle. Don't go to premix in the tank for the street. Premix works fine for race bikes that see the throttle pinned 95% of the time. On the street, you'll close the throttle at every downhill, at every light, and intersection. When the throttle is closed on a premix bike - there is "no oil" in the cylinders, rods, crankshaft, and most important the rings since oil and fuel are "one". You will seize and blame the bike when it was the lack of lubrication. The pumps were added back in the 60's to solve the starvation - it keeps oil flowing 100% of the time at different ratios and in direct relation to throttle opening. Setting as shown will keep your bike happy.

Regards,
Gordon

Here is a link -

http://www.3cyl.com/~mraxl/gt/manuals/gt750man/sr50.htm

[fuzzybutt]

i just got a 72' titan basketcase. cant wait till it's done....................................next year sometime lol

[buffalogt750]

Ok, there is an easy fix -here is how you adjust your oil pump properly.

See the diagram below and you'll notice there are two marks. One on the arm that your throttle cable attaches and one on the oil pump. You simply want those to line-up at with the bike at rest, idle, turned-off and hand away from the throttle grip (throttle closed) . The setting is controlled by the threaded cable adjuster at the pump. That should take care of it.

The oil pumps are absoluely bullet proof. The setting is designed to give you about 100:1 at idle and up to 30:1 at full throttle. Don't go to premix in the tank for the street. Premix works fine for race bikes that see the throttle pinned 95% of the time. On the street, you'll close the throttle at every downhill, at every light, and intersection. When the throttle is closed on a premix bike - there is "no oil" in the cylinders, rods, crankshaft, and most important the rings since oil and fuel are "one". You will seize and blame the bike when it was the lack of lubrication. The pumps were added back in the 60's to solve the starvation - it keeps oil flowing 100% of the time at different ratios and in direct relation to throttle opening. Setting as shown will keep your bike happy.

[/quote]



When the throttle is closed is there no fuel going thru the idle circuits? Road race bikes spend a lot of time on the race track with throttles closed. I also don't see how the oil pump could pump so much oil that it would make a carb slide stick. For one thing oil from the injector pump does not go thru the carbs. The diagram shown is for a gt750. Some of the old suzukis used a different method for adjusting the oil pump. Some had a sight plug on one carburetor. You removed the sight plug, opened the throttle to a certain mark, and then set the oil pump to a certain mark at that throttle opening. Make sure you're adjusting correctly.

[RRRToolSolutions]

I don't have a T500 of my own, so I don't have a shop manual. But, I did go to the parts fiche on-line to look at the pump and arm before posting the reply to his question - being responsible as I try to be. Did you check your data before coming on to slam confusion down on the table? His pump does have the arm and the mark fr alignment.

For the record, the amount of oil in premix with the throttle closed is nowhere near what is requires at the rpm turning. You have to remember, the crank, rods, and pistons are still working hard under decel - fuel/oil mix is almost completely shut-off. The only way the big-end bearings, crank, and rings get lubed. These pumps were the result of failures. All of the factories added them and the direct lubrication to the bearings because or fuel-mix problems on street driven machines. That research and documentation is all over the place.

Regards,
Gordon

[buffalogt750]

I do know that not all Suzukis use the gt750 pump adjustment procedure. If you had said that your diagram was that of a gt750 and that the t500 uses the same procedure there would have been no confusion. Sorry to slam anything down on the table.

[buffalogt750]

Still haven't addressed the problem of his carb slide sticking. I doubt it's the oil pump adjustment.

[RRRToolSolutions]

You are absoutely correct on the carbs - the oil pump has nothing to do with that. I only know of 2 bikes that pump oil into the carbs - the 1974 H2B (Mach IV) and the 1975 H2C - both Kawasaki 750cc triples. Let one of those sit long enough to allow the fuel to evaporate and you're left with a sticky, oily mess inside the bowls, jets. I've been there, done that.

No harm intended. Just trying to give advice - about all an old man can offer

Gordon

[RRRToolSolutions]

Look what I found - a service bulletin for the Suzuki T500 -

Use method "C"

Gordon

http://www.3cyl.com/bulletins/specification10.pdf

[buffalogt750]

That link would not come up for me, but I went to 3cyl.com and found the page. Click on "More service bulletins from Gunnar". Go to page 6. Then go to "Specification 10 oil discharge rate data" page 2 to find method C. "Specification 10 oil discharge rate data" page 4 confirms that method C is the procedure used to adjust oil pump on GT/T500 models. There's really nothing like having a model specific service manual. I hope that micron_52 reads far enough on this thread to get to the CORRECT adjustment procedure.

[buffalogt750]

Ilbikes, I'd also like to address the reliability issue of pre mix street bikes. If as you say, oil injection ratio is 100 to 1 at idle or closed throttle, that is less than half the oil of a normal pre mix ratio. How is this going to solve reliability problems? The main reliability issues were negligent owners doing incorrect pre mix ratios or forgetting to mix at all. Oil injection made the bikes more reliable because it made it more difficult for an owner to screw things up. It also made the bikes more user friendly and more competitive with the Honda four strokes which obviously required no mixing.