KZ Turbo Usage History

Do you guys know if it is possible to run a turbo setup on a KZ750 with keihin CV34 carbs? I still don't want to go fuel injection. I presume I will have to rejet carbs right?

CV carbs will need to have a pressurized plenum in order to work properly. It would take some work, but the ZRX1100/1200 guys with the Keihin CVK36's do it all the time. Even with mechanical slides the pressure plenum is required for blow through due fuel bowl venting.

Stroker Fan,

What did you buy....?

Cory

Here's my setup. The turbo was initially installed on the bike by a previous owner around 1980. Since then the engine has been apart and refreshed / improved.

• RayJay 370 turbo with ATP manifold and spider pipe.
• 1200cc Wiseco 8:1 turbo pistons.
• Welded crank.
• Stock cams with slotted cam sprockets.
• 31mm exhaust valves (stock is 30mm). 36mm (stock) intake valves.
• Heavy Duty main bearing and cylinder studs.
• The oil pump was modified to move the pickup to the bottom of the deep sump oil pan, and to optimize the flow (the pump case halves were lapped to improve the performance).
• MRE lock-up clutch with OEM-Style clutch plates and springs - this was after battling very heavy clutch springs and an extra disk clutch for a couple of years - it was killing my wrist and giving harsh control pulling away.
• Liska idler sprockets and tensioner assembly with a Tsubaki HD cam chain.
• The cylinder head gasket surface is ringed with piano wire.
• Dyna 2000 ignition hooked up to a boost sensor triggering the retard settings.
• HSR 42 carb fed by a 3-4 psi fuel pump
• Extra breather ports on the valve cover.
• Air/fuel sensor on the spider pipe and a readout on the handlebars.

Very Nice Jeff. I know the RayJays were popular back in the day, but when RayJay got bought out, the name and alot of info like comp maps are hard to find. Who O'Ring'd you head?

Cory

The wire ring was already done when I bought the bike.

I don't have any performance info on the RayJay - but I do have an original service document.

Here's a PDF copy. RayJay Manual

Joe at Pitstop can do the wire ring. Mine is in the block, When he fitted my MTC pistons he put new wire in the block for me.

Jeff.Saunders wrote: Here's my setup. The turbo was initially installed on the bike by a previous owner around 1980. Since then the engine has been apart and refreshed / improved.

• RayJay 370 turbo with ATP manifold and spider pipe.
• 1200cc Wiseco 8:1 turbo pistons.
• Welded crank.
• Stock cams with slotted cam sprockets.
• 31mm exhaust valves (stock is 30mm). 36mm (stock) intake valves.
• Heavy Duty main bearing and cylinder studs.
• The oil pump was modified to move the pickup to the bottom of the deep sump oil pan, and to optimize the flow (the pump case halves were lapped to improve the performance).
• MRE lock-up clutch with OEM-Style clutch plates and springs - this was after battling very heavy clutch springs and an extra disk clutch for a couple of years - it was killing my wrist and giving harsh control pulling away.
• Liska idler sprockets and tensioner assembly with a Tsubaki HD cam chain.
• The cylinder head gasket surface is ringed with piano wire.
• Dyna 2000 ignition hooked up to a boost sensor triggering the retard settings.
• HSR 42 carb fed by a 3-4 psi fuel pump
• Extra breather ports on the valve cover.
• Air/fuel sensor on the spider pipe and a readout on the handlebars.

Somebody else realized the advantages of spending time/money on exhuast side of a cylinder head for a turbo motor.
When I suggested this many times on here in the past I was told I didnt know what I was talking about ,It seems somebody else has had good luck fooling a smaller cylinder head into thinking its more efficient with oversize exhuast valves/stock size intakes since the exhuast side is what gets that turbo spooling.
That turbo doesnt care so much what the intake valve size is,its force feeding it.

That is true to a point. Too much turbo or not enough intake port volume can lead to excessive intake tract pressure which can work against the turbo causing a surge. You are correct on the exhaust as most N/A engine application are most efficient at a exhaust valve to intake valve size percentage of 70-76% typically. On a turbo charged application where the thermal energy cause exhaust gas expansion that is mostly regulated by the swallowing capacity of the turbine housing/wheel combination can find gains of an additional 5-10% of Ex/In size increase with corresponding port work.

Cory

NakedFun wrote: CV carbs will need to have a pressurized plenum in order to work properly. It would take some work, but the ZRX1100/1200 guys with the Keihin CVK36's do it all the time. Even with mechanical slides the pressure plenum is required for blow through due fuel bowl venting.

Stroker Fan,

What did you buy....?

Cory

Nothing yet, but iam really temped if i come across the right deal.

wireman wrote: Somebody else realized the advantages of spending time/money on exhaust side of a cylinder head for a turbo motor.
When I suggested this many times on here in the past I was told I didn't know what I was talking about ,It seems somebody else has had good luck fooling a smaller cylinder head into thinking its more efficient with oversize exhaust valves/stock size intakes since the exhaust side is what gets that turbo spooling.
That turbo doesn't care so much what the intake valve size is its force feeding it.

The person that helped me understand turbochargers was Frank Davis (Fast Frank) of Powerhouse Motorcycles on Long Island. I stuck with his recommendations. He has a turbocharged KZ1000 with NOS that's run 190+ mph in the flying mile - all without a fairing. His business specializes in turbo bikes.

wireman wrote:

Jeff.Saunders wrote: Here's my setup. The turbo was initially installed on the bike by a previous owner around 1980. Since then the engine has been apart and refreshed / improved.

• RayJay 370 turbo with ATP manifold and spider pipe.
• 1200cc Wiseco 8:1 turbo pistons.
• Welded crank.
• Stock cams with slotted cam sprockets.
• 31mm exhaust valves (stock is 30mm). 36mm (stock) intake valves.
• Heavy Duty main bearing and cylinder studs.
• The oil pump was modified to move the pickup to the bottom of the deep sump oil pan, and to optimize the flow (the pump case halves were lapped to improve the performance).
• MRE lock-up clutch with OEM-Style clutch plates and springs - this was after battling very heavy clutch springs and an extra disk clutch for a couple of years - it was killing my wrist and giving harsh control pulling away.
• Liska idler sprockets and tensioner assembly with a Tsubaki HD cam chain.
• The cylinder head gasket surface is ringed with piano wire.
• Dyna 2000 ignition hooked up to a boost sensor triggering the retard settings.
• HSR 42 carb fed by a 3-4 psi fuel pump
• Extra breather ports on the valve cover.
• Air/fuel sensor on the spider pipe and a readout on the handlebars.

Somebody else realized the advantages of spending time/money on exhuast side of a cylinder head for a turbo motor.
When I suggested this many times on here in the past I was told I didnt know what I was talking about ,It seems somebody else has had good luck fooling a smaller cylinder head into thinking its more efficient with oversize exhuast valves/stock size intakes since the exhuast side is what gets that turbo spooling.
That turbo doesnt care so much what the intake valve size is,its force feeding it.

kzrider.com/forum/9-chit-chat/588431-wireman-read-this

That stuff is old school thinking. There's more to making power than spooling up the turbo. But, then again, you have to know how to grind on the Inside of the head rather than the fins :lol:

Zmax Turbo Head

Thats cosmetic stuff there sunshine,that head was already ported. :whistle:
Some people actually pay attention to details.
Yeah thats old school thinking on the turbo head porting,but heres a news flash it actually works really good.
I think the picture of Jeffs friends bike proves that point with what its capable of.