TX750

[Charles13]

There is a low mileage mint 74TX750 near me and Kevin’s red bike has me interested in a classy stock looking refurb, I’ve heard that these long stroke motors are kind of feel like a cross between a Norton and a cb750, the chassis is very similar to the xs650 except it’s a step up in most respects, wheels, swingarm and electrical at first glance.
I’ve heard bad things about these but the owner says that the 74’s had all of the problems solved and are good for 100k miles, sounds a little optimistic but there is little to no info on these as they are so rare.
My friend had one when I was 14 and he used to let me ride it around the parking lot so there is a little sentimental element there.

 

[Raymond]

My two cents, the TX750 developed a bad reputation due to its crank frothing-up the oil, which led to oil starvation. I think Yamaha made changes, I guess they had to. Whether they fixed the issue I'm not sure but the bad reputation stuck and the bike was dropped out of the lineup. Others will have better-informed views.

 

[Raymond]

PS Correction to what I wrote above - it was the chain-driven crankshaft balancer arrangement that was guilty of frothing the oil.

 

[Charles13]

I do know through the little that I could find out that the 74 has a deeper sump, oil cooler and an eccentric adjustment on the balancer shafts. I believe it shares some components with the 650; valves, springs and cam chain adjusters (I think), the cam cover is one piece and has cooling fins, the starter motor is on the front and the 74 got double oil seals there so that also may have been an issue. The exhaust manifold is a little weird looking but overall it’s a beautiful motor almost aircraft looking

Edit: I found this and am going through it:
https://www.xs650.com/threads/tx750-madness.59445/

 

[Charles13]

Has anyone ever put an xs650 motor in one of these nice chassis?

 

[Mailman]

This one has been for sale in Phoenix for quite some time. It’s very nice looking and the owner claims that it had all the factory mods done to prevent engine damage.

https://phoenix.craigslist.org/nph/mcy/d/scottsdale-trade-1973-yamaha/7830614550.html

 

[MaxPete]

A guy in my class at university in the 1970s had a TX750 and he and I used to drag race up through the campus (I was on my '75 XS650B which was a little clapped out by 1979) and I could eat him alive - every single time.

That was the only one I ever saw in the flesh in Canada. It looked cool, but never seemed to live up to the promise of a high tech 750 IMO.

 

[Bob Wegman]

I worked as a tech in 1973 at a Yamaha dealer, The first year TX750, the copper color were a nice looking bike and were expected to sell well. They initially sold fair, but not as good as the left over XS2 650s ($1200.00) out the door. They had a lot of problems with the oil seal behind the ignition points leaking badly. I guess they had over pressurization of the crankcase from the frothing oil. That problem led to engine failures. Yamaha fixed the problem on the later year 1974 with a deeper sump and a fix for the stretching balancer chains. But the damage was done and they sold poorly. I have heard that the TX750 is a real nice bike after the fix was done. They are quite a bit heavier that the XS650.

 

[jetmechmarty]

I expect the ‘74 TX750 would be fine. I don’t believe I’d want it as my daily driver. Any machine will occasionally fail. This one has little to no support.

 

[Charles13]

This one has been for sale in Phoenix for quite some time. It’s very nice looking and the owner claims that it had all the factory mods done to prevent engine damage. https://phoenix.craigslist.org/nph/mcy/d/scottsdale-trade-1973-yamaha/7830614550.html View attachment 345811

I didn’t know they where worth that much, I have been looking at them on YouTube and they are very popular in Australia, I did also see a few that had different motors in them; they are a very nice chassis and look quite striking with different motors as you have to look at them whether you wanted to or not, because I think; the 750 motor is so individual that, as soon as you put something else in there it really looks different

 

[jetmechmarty]

as soon as you put something else in there it really looks different

I expect it also becomes worthless, but for parts.

 

[Charles13]

I expect it also becomes worthless, but for parts.

I imagine with a 650 motor in it you could make a beautiful looking standard that would garner more than a few double takes with the Yamaha badging and some nice paint and polish

 

[Charles13]

Could you picture one of these with a 650 in it?

 

[jetmechmarty]

Could you picture one of these with a 650 in it?

Not really. And I think it won't fit and look like it belongs. The TX750 engine is a work of art in the visual sense. It's unfortunate that it was released to the public before it was vetted.

 

[Charles13]

Not really. And I think it won't fit and look like it belongs. The TX750 engine is a work of art in the visual sense. It's unfortunate that it was released to the public before it was vetted.

Apparently it pretty much bolts right in, but your right the 750 engine with its tight fit, forward cant and compact fins has an aircraft mystique to it.
The one I’m looking at is a 74 model that is supposed to be very reliable and it only has 14,000km, they aren’t as fast as a 650 on the bottom but supposedly do 120mph very easy and are smooth as glass. I did have a BMW r60/5 that I enjoyed the heck out of and I feel these bikes are more down that path.
It’s a toss up between this complete running bike or another 2 86 Honda vf500f interceptors in a box that I would only file for parts for my minty 86 baby ceptor

 

[jetmechmarty]

Apparently it pretty much bolts right in, but your right the 750 engine with its tight fins and forward cant and compact fins has an aircraft mystique to it

They put a lot of thought into the aesthetics of that motorcycle. When I was 14, I wanted one oh so bad!

 

[bosco659]

This one has been for sale in Phoenix for quite some time. It’s very nice looking and the owner claims that it had all the factory mods done to prevent engine damage.

https://phoenix.craigslist.org/nph/mcy/d/scottsdale-trade-1973-yamaha/7830614550.html

View attachment 345811

Great looking bike. My friend rides one and he’s pleased with it.

 

[Mailman]

They put a lot of thought into the aesthetics of that motorcycle. When I was 14, I wanted one oh so bad!

Yeah when I was in high school a friend of mine bought one, I remember being impressed!

 

[Raymond]

Not really. And I think it won't fit and look like it belongs. The TX750 engine is a work of art in the visual sense. It's unfortunate that it was released to the public before it was vetted.

Stylistically, reminds me of the Laverda 750

Must be the sloping fins set close together?

 

[Charles13]

So much for that idea; it sold, I had messaged the guy and phoned him twice but someone must have beat me to it. Just as well I haven’t even started my new street tracker, and I do have a 73 cb450 that should cure the subtle custom/standard itch that Kevin’s red bike instilled