[arsenic]

I'm pretty sure they have short bronze valve guides also. Talk to them and see what they say. I have aggressive cams with valve springs and bronze valve guides. But SuzuikiRay made the valve guide shorter. It was part of the porting.

[cintidude04]

Im sure they do, appreciate your help guys. Gonna call it a night.

[loudnlow7484]

Well, not really. I knew about that long before I did the head work to the dream engine. I still ported it and back cut the OE valves. SuzukiRay told me porting it was a better idea, and I see no reason to doubt what he says.

Didn't you use a long-stroke head?

[arsenic]

Yeah, it's a long stroke motor. The head is a 98+ Katana 750. The cylinder block is a 90-92 GSXR 750 (long stroke). The rods are Crower rods for a long stroke. So yeah, it's a long stroke head. Oh yeah, MD's 771 is a short stroke. I really have no clue about those, I tend to stick with long stroke motors.

[loudnlow7484]

Yeah, it's a long stroke motor. The head is a 98+ Katana 750. The cylinder block is a 90-92 GSXR 750 (long stroke). The rods are Crower rods for a long stroke. So yeah, it's a long stroke head.

Bet those Crower's lightened your wallet quite a bit! What are you going to let it rev to?

[arsenic]

Not as much as Carrillo H-beams. I haven't decided yet. I have a Dyna 2000, so I can set the rev limiter too whatever I want. I'll let the Dyno tell me where peak HP is and as soon as HP drops off, I'll set the limiter. Unless it's dangerous to rev that high. Oh, the rods are custom made also. They have a 16mm wrist pin, OE is 18mm. The pistons are the same way. Rotational mass, every little bit counts.

[HemiKat]

Bronze valve guides dont hold up to mileage. (Except on BMW's, dont ask me how they make them last) Atleast not on car engines, not sure why it wouldnt be the same on a motorcycle, in fact it may be even worse with the high RPM's that the engine will see.

On the High Performace engines we ran, we tended to only get about 10k miles before they started to screech or rattle.

We did however port all our heads, but only the exhaust stroke and combustion chamber. Charlie Mallory, our engine builder that I apprenticed for has been building engines for 30 years so I dont have any reason to doubt him. You polish to combustion chamer to help get a complete and smooth burn and you polish to exhaust ports to help with flow. He was against porting/polishing the intake because he said the roughness helped atomize the air/fuel mixture, but a lot of different people have different theories on the subject.

[arsenic]

I 2nd what Hemi said about bronze guide not holding up to the mileage that OE guides do. You're building a max HP engine when those come in too play. So, you have to ask yourself, do you want tighter tolerances until your next valve job, when you replace them. Or do you want 200K miles on a max HP head. And it's more than 10K, at least 30K.

[scottynoface]

Porting and polishing is great, but yes, don't want it too smooth.

[05RedKat600]

I second that. It's good to poke your tool into the intake tract to help the flow out, but it's also good to leave it a bit rough to create turbluence so the fuel and air will mix better. Personal preference is to finish with 80 grit paper on a stick. Leaves a nice finish. Combustion chambers and exhaust runners get polished for good burn and high flow.

[cintidude04]

Will not be doing any polishing on this engine.

[arsenic]

I didn't polish the intake ports or the combustion chambers (although, they are hella smooth). I did polish the exhaust ports.

[md86]

I was referring to MD86.
So if say I were to use a set of 01-03 GSXR 600 throttle bodies with an OD of 38mm, the GSXR 750 90-92 intake boots would be a good fit.
Edit. My appologies, just double checked, the OD is 44mm.

Yup . I got the manual for the early 90's 1127 , and they use the EXACT carbs as the Kat 750's (BST36SS , though some Euro models got the 40mm carbs) , so I used mine , just jetted a bit differently (though oddly , not TERRIBLY different ) .

[HemiKat]

Yup . I got the manual for the early 90's 1127 , and they use the EXACT carbs as the Kat 750's (BST36SS , though some Euro models got the 40mm carbs) , so I used mine , just jetted a bit differently (though oddly , not TERRIBLY different ) .

Me too. Im running my 750 Carbs, oddly with bigger Pilot Jet and Smaller mains.

[spatula6554]