fuel tank interchangability

[maynard911]

A question for the gurus. I have not been able to find an answer using the search function. It is probably there but I have not found the right phrasing.

Do all xs650 tanks fit all xs 650 frames? Have the mount points stayed the same? I have an 83 that I would like to install a tank from the early, 72 or less, version. Any problems with the swap?

I was pretty happy with the look of my stock Heritage tank until it fell off the work stand and was dented beyond reasonable repair. Now, needing a new tank, my options have opened up a bit. I have always thought that the earliest tanks with the flat streak running front to rear had the best look.

 

[azman857]

I believe all XS650 tanks will fit xs650 frames. I put a '77 standard tank on my '80 special. Plumbing in the extra petcock was a job though.

 

[650Skull]

74 and later tanks are all interchangeable with all models from 74 -83. 74-79 Standard tanks are larger than the 78-83 tanks.

There were some differences in appearance with the Standard tanks. 74/75 have a raised cap and was carried over from the 73 tank. 76/77 have a newer style cap similar to the Special caps. 78/78 have emblems on the side of the tanks instead of decals as is on the 74-77 tanks.

70-73 tanks are a different length i think. The frames have different dimensions than the later Standard and Special frames

 

[jopower]

Can you expand on this? Maybe a nice list of tanks by years, capacities, details (petcocks, cap type and location, decal or emblem, tunnel clearance for coils...), and of course possible direct/mod needed swap years. Oh, yes... any other Yamaha (or ?) tanks that will go on a 650, like 400's and 750's. Pics if you got 'em?

(Me, I have a 78 SX650 with about 3 gal tank (2 vacuum petcocks, right side cap). Like to have longer legs, like 3.5 or 4 gal)

 

[azman857]

Standard tanks have a center cap and dual petcocks and are about 3.9- 4 gal. About another 50mile range than the Specials 3 gal. Bolts right on. Plumbing it a bit of hassle with the tight area. I do not recall if the '78's have 2 fuel feeds or not. That would make life a LOT easier if it does.

 

[bighairyralph]

The '72 and '73 tank are longer than the later tanks (I've never had a '71 so I can't say for sure but I'm pretty sure it's the same). I don't have a measurement for the difference but its around two inches. I'll measure it tomorrow if you want.

 

[jopower]

Sure! That 2" would require a seat pan mod or swap.

 

[CoconutPete]

I believe all XS650 tanks will fit xs650 frames. I put a '77 standard tank on my '80 special. Plumbing in the extra petcock was a job though.

I have an 81 tank on my 79 achieving the opposite. Now running 1 petcock split to the 2 carbs. Much easier and less moving parts to break.

I created a blockoff plate from an old petcock and a dremel for the 79' tank also. Never going back to 2 petcocks.

 

[fredintoon]

A question for the gurus. I have not been able to find an answer using the search function. It is probably there but I have not found the right phrasing.

Do all xs650 tanks fit all xs 650 frames? Have the mount points stayed the same? I have an 83 that I would like to install a tank from the early, 72 or less, version. Any problems with the swap?

I was pretty happy with the look of my stock Heritage tank until it fell off the work stand and was dented beyond reasonable repair. Now, needing a new tank, my options have opened up a bit. I have always thought that the earliest tanks with the flat streak running front to rear had the best look.

Hi maynard,
any XS650 tank after '73 will fit an '83.
Later model Standard tank filler caps that look like Special tank filler caps are different enough that they won't swap.
Early tank gas taps are manual, not vacuum and they don't swap neither.
You can blank off one gas tap hole on two gas tap tanks or opt to fit a Y-joint.
And how tall is your work bench?
I don't see a gas tank falling 30" onto concrete causing "Beyond reasonable" damage.
Unless you reckon grinding the paint off, torch annealing the creases, brazing flat head screws onto the dent centers,
pulling the dents back out flush with a slide-hammer, un-brazing the screws, filling the blemishes with 2-part body filler
and repainting as "beyond reasonable"

 

[bighairyralph]

I lied, the difference between the early tanks is 3/4". My memory had it grow It's still going to be necessary to make a new cross member for the rear mount. Here's a photo of the misalignment.

 

[1979XS650SF2F]

I lied, the difference between the early tanks is 3/4". My memory had it grow It's still going to be necessary to make a new cross member for the rear mount. Here's a photo of the misalignment.

I may have to make a homemade dogleg adapter which wont affect the frame or tank.

 

[Basementdan]

The '72 and '73 tank are longer than the later tanks (I've never had a '71 so I can't say for sure but I'm pretty sure it's the same). I don't have a measurement for the difference but its around two inches. I'll measure it tomorrow if you want.

I had a 73 tank on my 71