447 engine into XS2 chassis ?

[Grewth]

I've now collected almost enough cycle parts to build a XS2 rolling chassis.
But I don't have a XS2 engine to put in, closest I've got is a 447 engine from about '75.
I want to make the 447 unit look as much like the genuine article as possible from the outside.
I'm not really concerned about the con rod length or whatever on the inside.
Obviously anyone who gets close enough to read the engine number will know, but otherwise I'd like it to look stock XS2.
I've just bought a valve lifter thingy for the head, and I think I've got the correct cam chain tensioner somewhere.
Anything else that will give it away as a later engine ?

 

[Jim]

Minor, but the clocking on the oil filter is slightly different...

XS2 (256)

XS650 (447)

 

[Wingedwheel]

Minor, but the clocking on the oil filter is slightly different...

XS2 (256)
View attachment 326590

XS650 (447)
View attachment 326589

Jim, I had to go look and both ‘72’s are clocked like your pic of the 447. So are my ‘75 and ‘76. Maybe that was an XS1? I dunno.

 

[Jim]

Jim, I had to go look and both ‘72’s are clocked like your pic of the 447. So are my ‘75 and ‘76. Maybe that was an XS1? I dunno.

Dunno... here's a pic of the XS2 out of Tech.
Mid year change... maybe?

 

[Jim]

 

[GLJ]

Minor, but the clocking on the oil filter is slightly different...

XS2 (256)
View attachment 326590

XS650 (447)
View attachment 326589

The XS2 used the same clocking on the oil strainer as the later 447s. At least all the 256 XS2 and TX650 engines I've bought did. Just 70-71 had the different clocking.
I'm not sure if any of the 447 cam chain tensioners look like a 256 tensioner. When I built my last bike I used a 447 (1975 I think) engine in a XS2 and wanted to keep the tensioner looking original. I used a 256 tensioner and modified it to work with a 447 cam chain guide.

 

[GLJ]

View attachment 326592

I understand why you think that. My guess is the pic was made for the ad before the XS2s went into production. It also has no mirrors which we know wasn't true. Also a seat strap which I have never seen in person on a XS2. Maybe everyone took them off. It also shows a compression release lever for starting but no cable going to the left exhaust rocker cover. I think it's a rendition of what they were going to sell done with pre-production parts.

 

[GLJ]

Take my words for what they are worth. I've kind of specialized in XS2s. I've had one since 1976. But I have learned that I do not know everything about them

 

[Jim]

I understand why you think that. My guess is the pic was made for the ad before the XS2s went into production. It also has no mirrors which we know wasn't true. Also a seat strap which I have never seen in person on a XS2. Maybe everyone took them off. It also shows a compression release lever for starting but no cable going to the left exhaust rocker cover. I think it's a rendition of what they were going to sell done with pre-production parts.

I'm thinking you're right.

 

[Grewth]

Thanks Guys !
Now this is weird.
I Googled "Yamaha XS2 Brochure", and sure enough, all of Yamaha's brochures and publicity photos show the XS1 type oil filter cover.
But then Google images of the XS2, and all the real life bikes out there seem to have the late type cover as fitted by '75.
OK, these are real bikes which could have been rebuilt with later parts, but ALL of them ?
Finally, I Googled the '73 TX650 brochure and the cover is definitely the later type, so maybe the change over was during the '72 production run ?

 

[650Skull]

Yamaha did some funny things with their brochures. 74TXA brochure talks about the new frame and upgrades but has a 256 frame sitting in the brochure. It is on my laptop, took it out of the ID thread because of that.........looks like I need to redo the XS2

 

[DogBunny]

I want to make the 447 unit look as much like the genuine article as possible from the outside.
I'm not really concerned about the con rod length or whatever on the inside.
Obviously anyone who gets close enough to read the engine number will know, but otherwise I'd like it to look stock XS2.
I've just bought a valve lifter thingy for the head, and I think I've got the correct cam chain tensioner somewhere.
Anything else that will give it away as a later engine ?

I can think of four things. You've already mentioned the decompression valve cover (aka the thingy), and the cam chain tensioner. You will also need the correct engine breather -- the little box right above the cam chain tensioner. The 1972 breather outlet points straight back, the 1975 is angled down and has restrictors.
Finally, you will need the correct left-side case cover (aka the sprocket cover). There were all kinds of subtle changes which came fast and furious between 1970 and 1975. Square corners, round corners, cast-in shift patterns, oiler holes, and more. Read all about it here:
https://www.xs650.com/threads/oiler-hole-in-sprocket-side-case-cover.52932/

 

[Grewth]

I can think of four things. You've already mentioned the decompression valve cover (aka the thingy), and the cam chain tensioner. You will also need the correct engine breather -- the little box right above the cam chain tensioner. The 1972 breather outlet points straight back, the 1975 is angled down and has restrictors.
Finally, you will need the correct left-side case cover (aka the sprocket cover). There were all kinds of subtle changes which came fast and furious between 1970 and 1975. Square corners, round corners, cast-in shift patterns, oiler holes, and more. Read all about it here:
https://www.xs650.com/threads/oiler-hole-in-sprocket-side-case-cover.52932/

Many thanks !
I've read the thread about the sprocket cover, and now my brain hurts !
I think I've got the correct breather somewhere.
I've definitely got the valve lifter.
Clutch cover seems to be the same as the 447, so that's OK.
As for the sprocket cover, well, I'll just have to go with what I've got, until the correct item turns up somewhere.
I'm not planning on going on some sort of wild goose chase to hunt one down.
If I bide my time, the correct part will find me

 

[jay760]

The early engines also have an aluminium dipstick

 

[GLJ]

One other thing. You should get 70-73 rubber manifolds for the carbs. Later model manifold angle down. Need the straight early ones to match up with the early air boxes.

 

[Grewth]

The early engines also have an aluminium dipstick

Cheers !
I forget about that.
I've got one somewhere.
When I find it.

 

[Grewth]

One other thing. You should get 71-74 rubber manifolds for the carbs. Later model manifold angle down. Need the straight early ones to match up with the early air boxes.

Thanks again.
I've got to hunt some of these down for my XS1B anyway.
I've already learned the mistake of fitting cheapo Chinese items on my 650 Special.
Needed the Incredible Hulk to fit the carbs and they still didn't sit right.
Then I bought Tourmax, they were a perfect fit.
So are there any decent pattern manifolds available for the '70 to '73 bikes ?
I'd imagine finding original genuine Yamaha ones is nearly impossible.

 

[DogBunny]

Last time I looked, I think the only place I could find new 70-73 intake manifold rubbers was some place in the EU, probably Heiden Tuning, but maybe it was an EU eBay seller. They are pricey, as I recall. As for the metal "cages" that go around the intake rubbers, I think you have to buy used.