Yamaha YZF750R experience

[Wallowgreen]

Anyone here have experience with Yamaha 750's, 1994 YZF750R EXUP model in particular?

My son has been saving some pennies and has found one for sale he's interested in and I have no idea what to look for good or bad. I joined a Yamaha forum and asked the question there, so far nothing.

Any advice would be appreciated, thanks.

[El Giablo]

Beware of the exhaust valves.
They were prone to burn.
El G

[Wester Cooley]

That is Yamaha's Genital cylinder head with FIVE VALVES per cylinder on that bike!!!

Just costs more money to have valves adjusted and more money for a valve job when needed!

Another great idea that looked good on paper, but fizzled out in the real world.

[hillsy]

That is Yamaha's Genital cylinder head with FIVE VALVES per cylinder on that bike!!!

Just costs more money to have valves adjusted and more money for a valve job when needed!

Another great idea that looked good on paper, but fizzled out in the real world.

Didn't fizzle out on the R1 - certainly a good idea if you've ever ridden one

[hjfisk]

Didn't fizzle out on the R1 - certainly a good idea if you've ever ridden one

Agreed. ....

[Wester Cooley]

I stand corrected. Please forgive me Almighty Gods of Yamaha!!!

Never worked on a R1. Just FZR1000's.

And its shim under bucket. What a nightmare to do valve adjustments on. Its like working on a watch.

Plus not ONE Yamaha dealer ever has shims when you need them.

If you just ride them, and not work on them, they are great, I guess.

[Wallowgreen]

Well that seems like enough to put me off!

Thanks for the input fellas...

[hillsy]

Shim under bucket has been the norm for over 20 years. Service intervals are much wider than tappets, so you don't need to do then so often.

That's the price you have to pay for performance.

Back to the YZF750 - my brother in law has one and I've worked on it a bit. Fiddly to get the carbs on and off - general maintenance is kinda painful. They were built early on in the grand scheme of "new age superbikes" but were still a nice bike to ride. And fast. That 5 valve motor is sweet - regardless of maintenance / re-build costs.

[Sandy]

Well that seems like enough to put me off!

Thanks for the input fellas...

I had an FZ in the past and the valves aren't bad compared to most modern shim under bucket valves. At least on the FZ the valve cover is accessible by just removing the tank. 4 valves or 5 valves doesn't make a lot of difference if you have to pull the cams. At least on the Yamaha the recommended interval is 25,000 miles (42,000kms) between adjustments. Due to the light, small valves there seems to be almost no wear. On mine I adjusted them at 40,000 kms (I think it needed 2 shims) and at 100,000 kms they still didn't need any shims changed. Having been there I just don't understand what's so bad about it. After break in only one valve adjustment and 2 shims in 100,000 kms. can't be all bad. The FZs are certainly bullet proof.

[El Giablo]

Here is my YZF750/1000.
Fun bike


El G

[Wallowgreen]

That looks sweet Gordon, you still have it?

How would you sum up ownership - they troublesome to maintain and wish you never had it or easy to keep running nice? From what I've read on the web and in magazines, I've found no mention of them being a valve shredder or any other class problems actually.

I suspect maintenance is where my involvement is going to be!!

[Sandy]

I can't speak for Gordon for the YZF750R but I can for it's early cousin '85 FZ750. I owned it from 40,000 kms to 100,000 kms and was totally neglected when I got then I totally abused it with some track days, street racing and touring for another 60,000 kms. When I got it, it had hit a deer at some point and the fairing was broken as well the chain, which was original broke and damaged the clutch pushrod seal recess and was puking oil all over the place. Anyway after getting everything repaired and the servicing current I put another virtually troublefree 60,000kms on it. The only repairs and service that was done other than the usual fluid changes was another set of chain and sprockets at around 70,000, no shims needed after the 40,000 valve adjustment, clutch slipped a bit at around 80,000 kms (only at full throttle at max power band in top gear) so I just stuck new clutch disks in ($80.00), a failed ignition module at some point (swapped with a used one off an FZ600), and the stock exhaust rusted through at some point and I installed a pair of Supertrapp aluminum slip-ons. Bike ran as good the day I sold it as the day I put it back on the road. The FZR750 is pretty much the same motor in a much nicer chassis.

[El Giablo]

That looks sweet Gordon, you still have it?

How would you sum up ownership - they troublesome to maintain and wish you never had it or easy to keep running nice? From what I've read on the web and in magazines, I've found no mention of them being a valve shredder or any other class problems actually.

I suspect maintenance is where my involvement is going to be!!

That is from the "gone but not forgotten" list.
The 750 engine was replaced with a ThunderAce 1000 engine.
It had a bit of exhaust valve issues.
I am lazy.
That is why I have Suzukis.
Far less maintenance.
G

[GateKeeper]

I can't tell you yet on how good or bad the bike is, I just finished up the rebuild on this one, for now it runs well, I did not do the valves, but I will tear her down come winter and see what the valves are it, I will take the gamble.....

everything else on the bike was in OK condition, and compared from what I started with to what she looks like now, I am happy....

before



after

[Wallowgreen]

Thanks again fellas.

Been watching and reading your rebuild GK. Very nice job mate!

I thought they were strong machines, sounds like it might suit after all. Wonder if it's still for sale....