Suzuki 2 Strokes

Do you guys think I can use an oil pump from a T20 on a T200? they have different part numbers but the damn things look the same. I have 3 T20 oil pumps and I'm tired of the leak from my T200 oil pump (its not fixable tried many times)
I figure at least one of the others doesn't leak.

Keith what id do is to pull apart your old pump and the worst looking of the three other pumps you have and compare all the internals.
As long as they have similiar parts, bores and physical design theres no reason it cannot be swapped out for one of the other ones you have.
Of course you may find the final oil delivery settings may need to be recalibrated off any existing reference marks the old pump used.

On the T250 and T350 the pumps looks the same, but the output volume from the 350 is higher acording to the manual, I would guess that is the difference on the t200/t20 too...

premix...

Premix is a VERY BAD idea. You will trash the bottom end because of the injection setup for the main bearings and big ends. Suzuki uses injection to the crank and big ends AS WELL as to the top end. These bikes do NOT/NOT use a low rent single point injection at the intake like brand y nails use.
A word to the wise.....

wow did NOT know this...

glad i caught up on that

Rick is absolutely right about the premix idea. I figure if the 250 pump fits the 200, you can always adjust the slight difference in flow rate with the cable adjuster. The important thing is getting the oil to the bottom end as by design. Keeping a slightly visible blue haze should keep your motor happy. The grin factor is just a nice bonus. Cheers.
Fred

can premix effect the t500 the same way

zrs1919 wrote:can premix effect the t500 the same way

yes.

Did Yamaha have a different setup to lube the bottom end? From past experience, I know the pump setup on those is super simple. Just 2 simple lines feeding the intake ports ----- so they are essentially running premix.

Suzuki tended to find different solutions to the same problems.

Typical Suzuki design includes oil slingers to get the pumped oil out through the big ends to the main bearings. The bearings have an oil giude in teh outer race that matches the slinger.

That works great with pumped oil to keep oil in, but a switch to pre-mix means those same parts keep the oil OUT.

Yamaha, Polaris, kawasaki et al do not have those design features in quite the same way.

In addition, without pumped oil there is almost no way to get premix into the mains even if the oil slingers are cut down.

They can be converted but it isn't simple.

thank god for this post....i was going to run premix at the track hah...

I can remember selling literally hundreds of T200s, T20s, and TC250s because Suzuki oiled with 100% oil, and Yamadog oiled with gas before entering cylinders. We were selling 20 t0 1 of what the Y dealer was selling...just on that one selling point. How sweet it was!!!!

Um, that didn't really answer my question. How did Yamaha (and others) get lube to the critical bottom end bearings? And don't say they didn't. Every vintage show I attend has way more RD's than comparable Suzuki triples.

Sorry Chris, I only described the Suzuki triple system and didn't address your question.

The answer is that Yamaha arranged their oil feeds into the intake so that oil was drawn into the intake in teh same way that premix does.

If you inspect the bottom of a TZ running pre-mix and a road RD with oil pump, you will see that both have the same drillings in the bottom of the transfer ports directing oil down to the main bearings.

So the bottom end is oiled by what you might describe as variable ratio pre-mix. In this case it's mixed in the carb throat

Polaris used that same arrangement on their triple sleds with oil being fed to a drilling in the reed block.

Of course both the Polaris and Yamaha twins use lab seals not rubber seals and their whole bottom end architecture is different.

So changing a yamaha to pre-mix is a case of block off teh pump and mix some gas.

On a Suzuki it's strip the crank, modify some parts and rebuild. Then modify the crankcases as well.