New project

[Dvsrd]

Ther 1981 TZ250H was the first countr-rotating TZ engine

Yes, among the twins. But as far as i know, the 750 had a layshaft between transmission and crankshaft, so 4 shafts in total. And had opposite crankshaft rotation than RD and TZ twins.

[SoCal250]

Hmmm     

[teazer]

Correct, 750 motors run backwards. 
I want to say that originally only the OW31 works motors had TZ350g (3g3 casting) 6 port but I read somewhere that they were standard on later monoshock production bikes. 409-70 and 409-71 share the same RD type 4 transfer ports plus boost port.  Not sure what the later 6 port barrel casting number is but they may have been used on E and F models, but I have zero experience or documentation on those.  If someone has a set of those or E/F parts book, that would be interesting.

According to the parts books 409-71 (4 ports) was introduced on the D model in production December 1976, so a 77 model as we would know them.

On a twin the intake port becomes imprinted on the piston skirt. OK for low mileages and race motors that are often apart, but not ideal for a daily driver.

[teazer]

But enough about part numbers,  What is the project and when do we get to see a progress report?

If it's even half as good as your last one, it should be fantastic.

[Czakky]

Honestly I've been watching this forum because of this.

[Jspooner]

But enough about part numbers,  What is the project and when do we get to see a progress report?

If it's even half as good as your last one, it should be fantastic.

I'm going to keep you in suspense for awhile but I'll post more pics once I pick up the rest of it. It's going to be a major undertaking but should be really cool. I will tell you this much, the motor will be pretty much the same as my other one except for the pipes. I talked to Gary Braun (Retrodyne) about making them for me this time. 

[85RZwade]

  finally, something to wrap our imagination around! Thanks Joe

[Jspooner]

Part 2

[m in sc]

now we're talking. 

[preben54]

Hi Joe,I have a sneaking suspesion you turning cyl-180 deg around so exhaust is to rear and carbs up front ,that would be better for piston life but hard to fit in front, amI close Joe

[Jspooner]

Hi Joe,I have a sneaking suspesion you turning cyl-180 deg around so exhaust is to rear and carbs up front ,that would be better for piston life but hard to fit in front, amI close Joe

I haven't put that much thought into it yet but now that you mention it.............................

[EE]

Is that an FZR400 chassis Joe? Nice choice!! I like where your going!! I wouldn't go reverse cyl.. it's never proven to increase hp on our RD based case engines, TT saw it tried several times with guys using his cylinders and neither ever went faster. One of the reasons thought is that the later reverse cyl TZ's also had the crank rotating the opposite direction which may have aided the rev cyl intake flow, I've looked at it before but proper pipe length is an issue,  and carb clearance and issues ect..
.

[sav0r]

Rearward exhaust port sure makes packaging nice though.

It's never been preferred by OEM's because it's much easier to making a function airbox in the middle of the frame, where the intake is inherently protected.

[sav0r]

I accidentally quoted myself somehow.

[Jspooner]

Is that an FZR400 chassis Joe? Nice choice!! I like where your going!! I wouldn't go reverse cyl.. it's never proven to increase hp on our RD based case engines, TT saw it tried several times with guys using his cylinders and neither ever went faster. One of the reasons thought is that the later reverse cyl TZ's also had the crank rotating the opposite direction which may have aided the rev cyl intake flow, I've looked at it before but proper pipe length is an issue,  and carb clearance and issues ect..
.

Yes, it's an FZR400 chassis.........................as for the reverse cylinder idea, I don't really like how it looks anyway, so most likely NOT an option.