New XS650 project - looking for some advise

[xsdrew]

Hey guys,

I just bought a 1977 xs650, something that is a bit different for me as I come from a sport bike background, and I have some questions I'm sure some of you can help me with.

The story is this bike has been in a barn since 1987 and was sold with the intention to be a parts bike. The guy I bought it from wanted to restore it but life got in the way - he claims to have never done a thing to it besides keep it in a garage. So here it sits waiting for some love again. The really cool thing about this is it's only got 13,800 kms on it (8500miles).

My intention is to fix the bike enough to get back on the road safely and then smooth things out from there - IE: get it running and replace all rubber/brakes/wearable parts. There are some missing/broke components and bunch of things left unhooked that need to be sorted out.

Anyway, on to the questions:

1) My frame and engine numbers do not match. Should they? My engine number is "447-902906" I've looked online and can't come up with much.

2) In the middle of the below picture there is a vacuum barb in the carb spacer on either side of the bike. What should be connected to this?

3) The main electrical harness is missing from the bike, however, all the components seem to be left intact. Does anyone have any experience with xs650directs wiring harnesses? Is it worth while to buy one of those or try to put together my own? The PO did give me a main harness out of a later model 650 - But its not exact and has a fuse box, which as I have read on here, the '77s didn't have.

4) Do the keys match the ignition/gas cap/steering lock? It didn't come with keys and I'm trying to decide if I should try to get one made or just replace all the locks.

5) Has anyone tried a master cylinder rebuild kit? Is it worth while or should I just get a whole new one?

6) Obviously, the carbs will need some work... Should I buy a rebuild kit or just take them apart and clean? Are the gaskets on these things generally reusable or do they fall apart?

7) Wheel bearings and steering bearings... leave alone or replace?

8) If anyone has anything to add what should be checked/rebuilt on the bike before it attempts to go back in service I'm all ears!

Thanks.

 

[fredintoon]

Hey guys,
I just bought a 1977 xs650, - - -
Anyway, on to the questions:
1) My frame and engine numbers do not match. Should they? My engine number is "447-902906" I've looked online and can't come up with much.
2) In the middle of the below picture there is a vacuum barb in the carb spacer on either side of the bike. What should be connected to this?
3) The main electrical harness is missing from the bike, however, all the components seem to be left intact. Does anyone have any experience with xs650directs wiring harnesses? Is it worth while to buy one of those or try to put together my own? The PO did give me a main harness out of a later model 650 - But its not exact and has a fuse box, which as I have read on here, the '77s didn't have.
4) Do the keys match the ignition/gas cap/steering lock? It didn't come with keys and I'm trying to decide if I should try to get one made or just replace all the locks.
5) Has anyone tried a master cylinder rebuild kit? Is it worth while or should I just get a whole new one?
6) Obviously, the carbs will need some work... Should I buy a rebuild kit or just take them apart and clean? Are the gaskets on these things generally reusable or do they fall apart?
7) Wheel bearings and steering bearings... leave alone or replace?
8) If anyone has anything to add what should be checked/rebuilt on the bike before it attempts to go back in service I'm all ears!

Hi 'drew and welcome,
congratulations on finding a nice one that no effin' Vandal has tried to "improve".
1) Yes they should, the bikes left the factory like that, anyway. Not important, XS650s swap parts like LEGO.
2) Vacuum barbs operate the vacuum gas taps. Also used to balance the carbs.
If your bike don't have vacuum gas taps, cap the barbs off.
3) A later harness can be made to work. Compare the wiring diagrams in Clymer's or the diagrams available on this site to see the differences.
4) Keys should all be the same. The gas tank cap key should have a 4-digit number that will let a real locksmith (not the bimbo in the mall key kiosk) cut a new one.
5) Depends on condition. Some I've worked on just needed cleaning and even re-used the original seals.
6) Again, depends on condition. Some tricks:-
Work on the carbs inside a big cafeteria tray to keep those little parts from disappearing.
Grind up a set of screwdriver tips to be an EXACT fit in the soft brass jets' screwdriver slots.
Dump all those crosspoint screws and replace them with Allen screws.
7) Carefully check before replacing, they're a bit of a swine to change and could still be OK.
8) Upgrade the brake lines to stainless ones, the headraces to tapered rollers and replace the plastic swingarm bushings with bronze ones.
I'd also recommend drilling the front brake disk full of holes and installing a ScottOiler.

 

[xsdrew]

Thanks for the reply.

Just took a look at the petcocks and it is not a vacuum gas tap model. Obviously, the engine is from a different model; that's disappointing.

Is there anyway to find out what year it is?

EDIT:

I think I may have answered my own question...http://www.xs650.com/forum/attachment.php?attachmentid=25&d=1254687765

According to that chart its a 77-78 special engine? I didn't think they made specials in '77. That seems to be the only chart referencing a 447 engine in a '78. Could it just be a Canadian market thing?

 

[itsatoy]

Hey xsdrew, looks like you got a nice one. I wouldn't sweat the engine swap. There was probably a good reason for it and the xs isn't really collectible enough for that to effect value. It does pretty much make the actual milage an unknown though.

 

[nj1639]

The '77 model came with dual manual petcocks and shouldn't have the barbs on the intakes......no bigee.
Nice bike!

 

[xsdrew]

Thanks for the reply guys.

Unfortunately, I just did a compression test and it came out to 90 psi left and 100 psi right. I can only assume someone took the low milage engine out and swapped it in with their worn out one. I guess I need to reevaluate what I'm going to do with this bike.

 

[racerdave]

Put some oil in the cylinders and try it again. It will run on those numbers. Don't give up that easily. Get it running then check comp again.Engine and frame numbers do not match.

 

[ippytattoo]

Given the age and the amount of time it has been sitting those numbers aren't as bad as they would seem. Squirt a little bit of oil in the cylinders and retest you may see an increase in compression. Alot of times these old motors can see an increase in compression numbers from running them a little while (500 miles or so) to get the rings to reseat. Another thing you could do is pull off the carbs and intakes and the exhaust to get access to the valve seats and faces and clean them with a gun cleaning brush or something similar to remove any built up carbon that may be keeping the valves from closing properly. Also lube the valve stems where they go into the guides. Remove the valve covers and lube the valves and springs paying particular attention to the stems where they go into the seals and then set your valve lash as described in your manual.

 

[nj1639]

My '77 was seized from sitting for 25 plus years outside under a shed roof. Once freed up the compression was 85/89 or so. Got her running and with no funny engine noises.....haven't checked compression since....starts first or second kick, no smoke and runs great. You may be fine...get her cleaned up and see what she'll do.

 

[xsdrew]

Definitely not going to give up on the old girl! But, I was thinking I was going to have to reevaluate my plan. Not so sure anymore.

So, I put some oil in the cylinders and after a few tries I got the numbers up to ~98 and ~112. I then used my boroscope to take a look at the cylinder liners; no noticeable scratches or scoring that I can see through the scope and there does not appear to be a ridge on top of the bore. The cylinder walls do have a slight off color to them. Not pitted/corroded but have a rust tinge to them - could be causing the rings not to seat properly. The pistons also have a decent layer of carbon on top.

I think for now I'm going to try to get it running as is and reassess later.

 

[Sci85]

Incorrect valve clearance will also cause low compression numbers. Do a proper valve check and clean and I bet they come up.

 

[fredintoon]

Thanks for the reply guys.
Unfortunately, I just did a compression test and it came out to 90 psi left and 100 psi right. I can only assume someone took the low milage engine out and swapped it in with their worn out one. I guess I need to reevaluate what I'm going to do with this bike.

Hi 'drew,
hold back on the major teardown, you may be OK yet.
Engines that have not run for a while do tend to give low compression test numbers.
Put a couple of hundred miles on the bike, which will of itself reveal any other little problems it may have, before you do another compression test.
The numbers may have improved.

 

[5twins]

That '77-'78 production date for your motor would be consistent and normal. Like cars, bikes begin production of the next model year in the fall of the previous year. I think you may have gotten the '78 motor and carb package. Those vacuum nipples started in '78 and your carbs appear to be a '78-'79 set.

 

[XSLeo]

I will add a few things.
On the carbs, don't buy kits. Most of the stuff in kits aren't the right parts for your carbs. Read the carb guide www.amckayltd.com/carbguide.pdf
Do the teardown, clean and inspect, then buy just the parts you need.
On the M/C rebuild kits, I've not had the best of luck, On Ebay you can buy new M/C's for the same or less than rebuild kits. Just get a new one. The calipers, rebuilding is easy. Not many parts. usually just a tear down clean and reassemble is all you need. Know more when you tear down and inspect.
Wheel bearings, should be ok. They last fairly well. Steering head bearings. They are loose balls and races. They get worn in a straight ahead pattern. As you turn the bars and it feels rough, like notch then they should at least be removed, cleaned, inspected and greased. Replacing with new tapered bearings is a good up grade but if the stock stuff feels ok it can wait.
The swing arm bushings are often worn, but could also just be a loose pivot bolt. Try properly tightening the pivot bolt first.
If the tires are over about 6 years old, replace them no matter how they look. Old tire are dangerous tires. You can tell how old a tire is by reading the DOT number on the tire. The last few digits are in an oval. If they have three digits in the oval they are very old tires, made before 2000. after 21000 they had 4 digits. The first two are the week of the year, the last two the year they where made. As in 2704 That means the 27th week of 2004.
Don't worry to much about the engine until you get it so you can ride it. Then Ride it for a few hundred miles to find out just what might be wrong. Fix things as they come up. Ride the rest of this year. This should be plenty of time to find out what it needs.
If it does need some engine work do it during the winter.
Leo