My 1978 Yamaha XS750 SF Project

Hi all,

I got this bike in 1987 and we grew up together… too many fond memories.
I don’t even now how many kilometers I’ve done with it, probably +200.000…
750cc, 3 cylinder DOHC, 64bhp @ 7,500rpm
With three disc brakes, final shaft drive and cast aluminium wheels, it was quite “haute gamme” at it’s time.
Has had numerous restorations, last one in 2013, did all but not the top end of the engine.
Now, with time to spare, it’s time has come.
.

Pistons, ring and cylinders are worn…
They were rebuild it 1997 and have something like 100.000km on them.
Valve stem seals were quite hard and it was burning some oil.
I have a spare cylinder block that is in very good nick, waiting for new rings and a gasket set to arrive.
.

Now, why is that one intake valve black ?
As I said, rings were worn and valve stem seals were hard, too much oil coming in the cylinder?
Otherwise the head is in good shape, cam journals are clean, so it will be reused.

Will keep posting as I progress.
Best,
Aristides

2 Likes

Incredible you keep it for so long. When I was young and into bikes I couldn’t wait to trade up to the next one.

Only one I would like To have kept now is a Suzuki GS750. Beautifully handling bike.

Stew

I had one of the first Japanese bikes exported to the UK, a Yamaha YL1 twinjet. A 5 speed 100cc twin carb two-stroke - the first two-stroke with oil injection AFAIK.

Price new was £169 and I got it on the never-never.

I had one of those at the age of 14. I think they were actually something like 99 cc.That way they qualified for the under 100 cc. rule. Anything bigger required the operator to be 16 years old. I do not remember them being a 5 speed. I thought they were 4 but it was a long time ago. You could reach around the speed of 65 mph on flat ground if you lay down flat along the bike with your feet straight out behind to cut down on wind resistance.

In the UK you had to be 16 to ride any kind of motorbike (but you could drive a 3-wheeler at 16 too) AFAIK the Canadian YL1 model was 90cc. Maybe the YL1 was 4-speed, it was a long time ago!

I got mine in 1967 to replace my old Vespa, (which had itself replaced my 1949 BSA Bantam that cost me a fiver.)

But there was a weight limit of 700Lbs (I think it was about that) which is where the Reliant was at 699?

Reliants at the time had the image of an Invalid Carriage …(at least in my crowd) so no go on those.They were all Blue too as I recall

What we all wanted in a 3-wheeler were Orange Bond Minicars, kick started and no reverse but so what, you could pick 'em up!

(I suppose the Isetta or Messerschmidt qualified as sorta cool-ish, maybe the Messerschmidt more than the Isetta)

Hi Aristides,

Were you aware that we have a dedicated Motorcycles category on Jag-lovers now?

https://forums.jag-lovers.com/c/motorcycles/

Just FYI.

Gunnar
(Admin)

1 Like

Cleaned, paint striped and everything polished.
Can’t even count you how many hours…

1 Like

Man, I just don’t have that kinda patience!

Believe you me, I will never do it again…
But the result is very satisfying!

1 Like

Bling bling…

Please DON’T, at least not on a JagLovers site.
Not aware Jaguar ever made a motorcycle, let alone one made in Japan (or from Chinese factory), so instead promote your YAMAHA efforts on a site possibly more interested.

Well Jaguar started with side cars so theres always that tenuous connection.

1 Like

Roger, did you notice, this is posted in a forum, titled MOTORCYCLES?

1 Like

Now, if you hit all that polished aluminum with corn starch… you’ll get it even shinier!

Roger,

(Edit: My previous comment about racism removed, with apologies to Roger.)

Nick and I have decided to welcome the discussion of motorcycles on Jag-lovers, in part due to the history of Jaguar’s founding. That is why we created the Motorcycles category. If you’re not interested, I suggest you avoid this category. You can even mute it in your preferences, so you won’t see it.

Just like we welcome the discussion of all sorts of cars and other machinery in the Pub, we welcome the discussions of all brands of motorcycles and sidecars here in the Motorcycles category.

For your information, Jaguar Land Rover does manufacture cars in China.

Gunnar
(Admin)

2 Likes

Really?

Learn sumfin new, every day!

Indeed.

1 Like

I hadn’t, no, but now being made aware of this new Category presumably recently introduced, and after I set up my category settings, I have now ‘muted’ the category.
Took the opportunity to ‘mute’ a couple other categories similarly of no interest.