93-gsx750f

[Buffalo Bill]

Glad you spoke up…

Experience with the GS series motors tells me that the GSX series motors are probably just as well designed and as long lived.

Cool! Because the side decals on mine are scratched up and I can't find them to buy, I'm thinkin' of different color combos including black with gold stripes but resembling one of the factory designs as best I can do it. I may stick with this color but paint on a copy of the side decal.
From looking at the diagrams the GSX engine resembles the GS engine closely.
Bill

[Buffalo Bill]

OEM tool kit?

I can't believe it but, yes I like having the OEM tool kit under the seat. I like the complete OEM thing. So I bought one off eBay, only $40 with S&H.
I once repaired a helmet visor with the screwdriver and pliers from my GS1100G during a ride. So you never know.
Right now I'm waitin' on bikebandit to deliver some merchandise.
The bummer is my GS550T still ain't runnin' right so that's distractin' me.

[Buffalo Bill]

Good comp. test!

Cleaned out the rusty tank good. I found plenty of residue in the carb bowls and cleaned those up too. I wire brushed the headers real good and painted them, all OEM. I took the old spark plugs out and they showed ideal burn residue.
Looks like mostly all it needs now is new valve cover gaskets and tires.
The big news is: Compression test came out great! Average of 177psi. wet.
I just got a compression guage that came with an extension to reach down to the plug hole and did a cold test.
The guage had 2 extensions. I used the screw together version with a long hose first and only got 47psi and was bummed out. I was considering parting out the bike and looking for another.
Then I tried the shorter extension with a rubber wedge tip and got the higher results.
It must have been that the longer combo extension had a large volume that absorbed most of the pressure.
The bike is on it's way to the street!

[jetta90]

That is a great compression number Buffalo Bill. If all your cylinders are coming in around the 177 level I would have to say that is quite healthy indeed.
How many miles on the bike?

[Buffalo Bill]

Next check, valve clearance & adjustment.

That is a great compression number Buffalo Bill. If all your cylinders are coming in around the 177 level I would have to say that is quite healthy indeed.
How many miles on the bike?

Mileage is 16933.
I feel kind of a fool after watching a pristine '96 750 in TN sell for just $1500 on eBay. Now I'm following another pristine '96 750, original owner, only 8900 miles and that one is just 80 miles from me. Could go for less than $1500. As I read someone else say: “There's always another bike out there.”

[LeeGS550E]

I have a '91 750. I run Bridgestone BT-016's and really like them. Used a 150/60 R17 on the rear. I would recommend them over BT-45's, but those are good tires too, just not radials.

[Buffalo Bill]

Will buy radials…

I have a '91 750. I run Bridgestone BT-016's and really like them. Used a 150/60 R17 on the rear. I would recommend them over BT-45's, but those are good tires too, just not radials.

Thanks. Right now I'm mostly settled on Michelin Pilot Power radials, the same prices as BT45's but people rave about the stickiness and mileage.
Fact is here in the flat Midwest we mostly just wear out the middle of the tire.

[Buffalo Bill]

Valves…

Checked and adjusted all the valve clearances today, lookin' good.
These engines have adjustable rocker arms so it was easy to do.
The PO believed the engine was burning oil, but all the spark plugs were clean, the compression checked out great, and the valves checked out good. So it must have been oil seeping out the valve cover gaskets and onto the headers. Have a new set to go in, and that's the last test.
I can start reassembling the bike, start it up and go.

[Buffalo Bill]

It Started! Ready to be fitted out…

Yesser, it started up, ran rough on maybe 2 cylinders, put out plenty of gray smoke and the new header paint smoked up good just for help.
But it kept runnin' and gettin' better. All 4 cylinders got goin' and all the carbon burned out of the exhaust system and the paint stopped smokin' too. I closed off the choke and raised the idle.
Then it got real good, with a clean exhaust. There's plenty of power in that engine. It's got the OEM exhaust system, so it's got an understated sound like a GS, not tuned to be loud or sound wicked, but that engine has power. Revs up to 8000 right now, I didn't want to go past that.
Ordered a new battery, needs tires too, registration and insurance. $500 right there.

[Buffalo Bill]

Damn, got a knock in there…

Seems to be a knock sound coming from under the valve cover someplace.
I started it up again and used a hose for a stethoscope to locate the source of the knock.
It's coming from the location of the #4 exhaust rocker or the end of the camshaft. That's where the sound is loudest.
Could it be the exhaust camshaft walking or knocking sideways?
Thanks.

[GregT]

As you'll have seen when you did the valves the rockers are located sideways by springs - lift the cover (again) and check no springs are broken or missing. Could also be a cam cap not down correctly.
Generally endfloat on the cams isn't a problem on the air/oil GSXR motors.
You do realise your motor is a detuned GSXR 750 J...detuned mainly by lower lift cams. The J cams drop in....

[jetta90]

How you making out with the top end knock Buffalo Bill? Any luck finding the issue?

[Buffalo Bill]

Has to be opened up…

How you making out with the top end knock Buffalo Bill? Any luck finding the issue?

I was compelled to ride the bike, so I put all the panels on and took it out for a few miles. The bike had power, but something is wrong. The noise was privately embarrassing for me at stop lights.
I plan to take the cover off and spin the engine with the starter. I just might be able to pinpoint the sound and problem. Could be messy.
If a cam bearing is bad than the whole head is bum.
Will do this weekend

[Buffalo Bill]

Bummer…

Is that a worn cam lobe? Looks like the cam, and cam follower will have to be replaced. That's the #4 exhaust cam lobe, knarly.

[davidduarte]

what would cause that, a stuck, or sticking valve?