Suzuki 2 Strokes

I've bought a '72 T500 to build a race bike from. Everything I see says to keep the oil injection. that would be fine except I have no lines or poppet valves. the pump is there on one engine but not on the spare engine. I am racing a RD400 now that runs premix as my KTM does. I would like to just run premix in my 500 too if I can find out how.

Now before I get chastised for removing it, remember I don't have it, just a pump and it doesn't look good. I have not found any of these parts available any where. I am going to tear down both engines and have the cranks built and do the 1400cc trans oil mod and build up from there.

If I can find someone that has actually run premix in one of these bikes and find out the mods needed it would be a big help to me getting my bike on the track. My KTM simply has the bearings open to inside and there is no slot in the bottom of the rod but there is a little bit of room between the rod and the flywheels. My RD has a hole drilled from the transfer ports down to the outside mains and there are 2 center mains, one on each side of the center crank seal. Best I can tell the T500 the center bearing gets lubed from the trans so I don't have to worry about that one, only the outers and the rods.

Thanks,
DC

These guys (no connection) sell poppet valves

http://www.ebay.co.uk/itm/Suzuki-T250-G ... xy63FSnMu9" onclick="window.open(this.href);return false;

I have bought a set and run them for 10 000 miles with no problems.

If you search this site you will find references to people who have made up new lines using thin pipe, nylon blocks and epoxy.

I think the alternative is to buy a second hand set of lines, because as you say, the internet suggests switching to pre-mix is a pain

Hello DC,

I run pre-mix in my T500 race engine. If you are having the cranks re-built you are 95% of the way there anyway, basically you need to omit the oil flingers when re-assembling the crank. As it turns out I am having a race crank re-built by Pete Odell tomorrow (28th Aug) so I will endeavour to take some photos & video to show what needs to be done (in case my simplistic description has subtleties I am ignorant about )

Cheers Geoff

Hello DC,

My crank was re-built by Pete Odell on Sunday. Yes, basically all you need to do is omit the oil flingers on assembly, BUT, you need to replace them with an equal thickness shim so that the outer main bearing maintain their spacing on the crank ends. A, not very good photo below, shows the two spacers on my crank (Timing side) One is the regular thrust washer (P/N 08211- 25401 (P/N 08212 - 25401 for M model)) and the second is one of the same which makes up for the "PLATE, oil guide" (in Suzuki parts book terminology P/N 12511-15000)



Cheers Geoff

Thanks Geoff, this is what I needed was advise from someone that was doing it and the fact that it is your race bike is all the better. I will be getting the crank built, it all fells good and it is a low mileage bike but it has been sitting a long time and if nothing else I feel the seals need to be replaced.

DC

Hello DC,

Take note of the which seal face is to the outside of the bearings and ensure the new ones go in the same way. Don't ask me how I know you can install them backwards .

Good luck

Geoff

Geoff, I read your build up of a crank with some pics. Looking at the big end of a rod you had go bad I saw notches ground into the big end of the rod that I guess are to allow premix to get into the rod bearing? Can you give me details on these cuts? Did you find out what caused the bearing failure?

Thanks.

Dbc105 did you do the conversion to premix on your T500? I am hoping to do the same soon. Are you rebuilding the crank yourself or sending it to a shop somewhere. Everyone tells me not to do it but I can't stand that pump and those delicate oil lines. Plus I will be riding the bike mostly at trackdays so not a big deal. I look forward to hearing how it works out

I have converted my T500 to premix and been running it that way on the street for several years.
As previously stated, I removed the oil slinger plates, and fitted shims in their place.
I also took the precaution of drilling a drain hole in the transfer port cutaway directing oil into the outer main bearing cavity.
This was quite a common practice on bikes designed to run on premix, so I thought it a good idea.
I am using 40 to 1 synthetic mix, and the bike seems quite happy with this.

Andrew

Forgive my ignorance, I'm just a street rider, but what is the advantage of running premix? I must say that 40-1 seems lean to me, but I'm sure that's more oil than would be burnt using injection.

titan performance wrote:Forgive my ignorance, I'm just a street rider, but what is the advantage of running premix? I must say that 40-1 seems lean to me, but I'm sure that's more oil than would be burnt using injection.

For a street bike I would retain the regular Suzuki CCI. It feeds fresh oil to where it's needed and you don't need to carry a spare container of oil or measure for those visits to the petrol station. So, no real advantage for pre-mix over the CCI.

For racing the advantages are more precise/known control of the oil content (I use 20:1 or 25:1. Yes 40:1 seems rather mean). Also the issue of an oil pump failure/fractured oil lines etc. is eliminated i.e one less thing to fail. You don't need an oil tank, so a small weight saving (although leaving out the pies'an pints for a month would result in better results on that one )

It would be interesting to hear what sort of oil ratio (on average) you get with the pump.

Cheers Geoff