Carb rebuild kits?

[Ivan]

Just took in for repair a 75 T500.... I'll have a good look at the carbs this coming week.

Ivan

[Ivan]

73 and later carbs have no main air jets..... So this leaves the bowl venting as the only significant difference in the carbs circuitry.

I looked at the location of the vent hole between the 69-72 32's in comparision to the vent hole on the 34's

The hole on the 34's is much larger and also more in a direct line (more easily affected) from the incoming air....

Next comes the actual dyno tests with these vents open and closed to the atmosphere....


Ivan

[Vintageman]

Tz and Ivan

Please clarify, the early (69-72) 32 mm carb has a homo vent and so does the later (73 - 77)?
Neither has air jet

I read somewhere that the intake floor was lower on the early T500 ( so the author guessed). If true even a 1-2mm or so could be why the earlier has more top end and less bottom torque. I wonder how much diff the intake divider makes?

I wish I had later cylinders to measure ( I do it is on my bike right now). I did measure (and post the earlier port specs).

I bought a set of earlier cylinders. I really want to try the characteristics of the early bike.
If the carbs are different I may need to buy a set too.

[Ivan]

73 and up carbs are externally vented (non H-P)

69-72 carbs are internally vented (H-P)

All T500 carbs have no air jet.

I believe that the biggest contributing factor to the earlier bikes better top end is from a shorter intake tract... a mm or 2 in the intake duration will have less of an effect than the intake length.


Ivan

[akazoroe]

Any progress on the T20 kits?

[Ivan]

Dyno charts are up.... just a few minor things and I'll be packaging them next week.

http://www.ivansperformanceproducts.com/T20.htm" onclick="window.open(this.href);return false;

So far, I have not been able to source needle and seat assy's (OEM)

Bowl gaskets are no problem and I have them in stock.


Ivan

[mario03srt]

Ivan,

I'm very interested in a tuning kit for my 69" T500 with orig 32mm carbs. I have pod filters, Jemco Chambers, polished ports. I am currently running a 35 pilot, 160 main, jet needle up 1 position (clip down 1 slot) as initial starting point.

I will follow this thread and your site.

Thanks,

Marion

[akazoroe]

So far, I have not been able to source needle and seat assy's (OEM)

Damn...I really need those.

[Ivan]

Call Paul Miller...

860-828-1771

They may still be available from Suzuki...


Ivan

[ConnerVT]

Is this it? Or maybe they have one similar?

https://www.denniskirk.com/mikuni/vm28- ... 170335.sku

[akazoroe]

Is this it? Or maybe they have one similar?

https://www.denniskirk.com/mikuni/vm28- ... 170335.sku

Not sure.

Ivan does that look right?

[Ivan]

Not even close....

They are the same as Yamaha YDS3.... I think it's 7mm thread.. Gonna measure it today.

The hole size is 2.0


Ivan

[Ivan]

This is what they look like...


http://www.ebay.com/itm/YAMAHA-YDS3-YDS ... es&vxp=mtr" onclick="window.open(this.href);return false;


Ivan

[ConnerVT]

Oh well. i was taking a guess, not knowing which bike we were talking about. The one I linked are what I put in my T500.

[Ivan]

Thread size for the T20 needle & seat assy is 7mm X .75

These may still be available from Suzuki as are the float bowl gaskets.


Ivan