Head question

[2scars]

I have 1991 750R (m) with a ruined head that I received in a parts lot.  Would the head from a B6 or GSX6F work to replace it?  Would the cams from 750R fit in the 600 head?  And, last but not least, what work would need doing, if this all would bolt up, to make it perform like the original 750R motor?

 

Thanks. 

[Gixer1460]

No, No and No. Work - loads if not impractical!

Edited October 14, 2021 by Gixer1460

[2scars]

Damnit, I figured that the combustion chamber would be too small, even if the cams would work.  Combing through the Frankenstein write up in the vault gave me some hope...

 

Blast...

[wraith]

Valves are smaller and ports are way way smaller

[Gixer1460]

12 hours ago, wraith said:

Valves are smaller and ports are way way smaller

And I believe more critically - the bore spacing and consequently the cylinder stud spacing is all to cock also!

[dupersunc]

The bandit head will physically fit but the 91 cams wont work, and I believe valves are smaller. 

Gsxf head will not work as the cam chain tunnel won't line um properly.

You options are, a 85-87 750 slabby head with  matching cams and followers,  a 90 750 slingshot head, cams and followers, or a 91 750 head, your cams will work with this.

Anything else will require skilled machining and or welding to work. 

[wraith]

Just for info lol 

The 85/86/87 and 90/91 750 barrels will fit the b6 bottom end.

I'm told and hope, as will be fitting some on a b6 bottom end in the future.

[2scars]

I have a 750M (long stroke) motor with bad head, a suspect B6 that was free, and a GSX750f motor that is likely rusty in the cases.  Trying to make something out of nothing.  Not many of these oil boilers turning up these days in the States.

 

Edited October 25, 2021 by 2scars
clarity

[Upshotknothole]

5 hours ago, 2scars said:

I have a 750M (long stroke) motor with bad head, a suspect B6 that was free, and a GSX750f motor that is likely rusty in the cases.  Trying to make something out of nothing.  Not many of these oil boilers turning up these days in the States.

 

Where are you at in the states? I'm constantly looking for parts on the west coast. Usually a couple of GSXR 750 engines on craigslist.

[2scars]

Virginia, I have  guy in TN that has alot of stuff, but nothing for the long stroke motor.  I picked up a set of BST38s from him recently, and maybe a rear brake stay soon.  I thought I had a Teapot 1100 motor but the guy has decided to try and get the bike back on the road.  I don't think he has the disposable cash to do so given the state of the bike as a whole.

[Upshotknothole]

Yeah, even on Eblag there isn't much anymore for these bikes here. Half the time the best option is just to find a cheap project bike and pick it of parts.

[2scars]

There is a person on FB marketplace in Lynnwood, WA that has a complete bike in parts for $1k if you are looking.  Oil cooled 750 and good fairings/tank.

Edited October 27, 2021 by 2scars

[2scars]

The local guy with the relatively complete 1990 GSX1100F has gotten back to me and decided to sell.  So looks like I have a motor for a GSXR7/11 after all. 

Edited October 27, 2021 by 2scars

[wraith]

Much better than playing with bits of a 600/750 motors 

[2scars]

2 hours ago, wraith said:

Much better than playing with bits of a 600/750 motors 

Truth.

 

[2scars]

Can anyone point me in the direction of some knowledge on the tin top 34s that come with these motors?

 

[wraith]

1 hour ago, 2scars said:

Can anyone point me in the direction of some knowledge on the tin top 34s that come with these motors?

 

In what way  

They are a very good carb, the turbo boys will taire your arm off for a set, and they work very well on air cooled GS 2v and gsx 4v motors.

I've get a set of gsxr750 38mm cv on my gsx1100f motor and they are great.

[2scars]

Well, I have two sets of 38s, but one has worn needles and slide guides.  If the 34s are serviceable on this particular bike, are they basically the same design as the BS34s used on Kwaka Zeds?  The bike I'm picking up has the V&H exhaust and pods, so possibly already setup with a DJ kit.  I can't wait to tear it to bits and get the good stuff off...