Repair or Part Out a 1982 Vision?

[C Clement]

Hello all,

I have had a 1982 Vision with 30k miles on it I picked up cheaply hoping to get up and running.  I replaced the TCI and have spark to both plugs but can't get it to kick over even with starter fluid.  I cleaned the carbs including the ultrasonic bath.  Then I finally got smart and checked the compression, now I realize the compression test is supposed to be done on a warm engine but that is not currently an option. The front cylinder measured 105 psi and the rear about 85 psi.  I have not bought a manual yet as I was not sure where things were going with the bike but those numbers seem really low to me. My original plan was to use the bike for a test bed for a Microsquirt fuel injection system with the throttle bodies from a CBR1000.  As the Microsquirt system controls the fuel injection and the ignition, I thought it would eliminate any problems with the existing ignition system.

The question I have is whether I should proceed with the repairs or if I should move on to something with better parts availability?  The bike has a fair number of good parts that could revive a few Visions, i.e. rust free exhaust, good starter, good instrument cluster, etc.

I just thought that I better ask the experts.

Thanks for all the information you all have posted.

Craig

[Re-Vision]

Glad you are here Craig, I wont pretend to be a mechanic but if you have fire, do you have fuel? Can you see fuel being sprayed into the carburetors when twisting the throttle? Checked the plugs? There are enough people here with know-how and parts to get your bike up and running. Recommend that you hold off on parting out bike until you determine what your problem may be.    BDC

[The Prophet of Doom]

Generally the XZ550 is a better choice of bike than many to resurrect, the bike is relatively straight forward, has a good strong engine, and many parts you can get from people here at reasonable prices.  There are a few regularly occurring faults, but they are well known and mostly easily fixed.  It's also one of the coolest bikes Yamaha ever made.

The are some manuals available free on diplodocs.com, but PM Lucky to buy a copy of every known manual and review on CD.  The Haynes manual (on the CD) has quite a good section on troubleshooting.  This forum has a hundred or so people who have been there, done that - the support you will get here is outstanding, and generally better than you will get at the dealer.  The trick is to be reasonably detailed about your problem.  What are your symptoms, what have you tried to fix it.  Unbelievably, people here do not get sick of answering the same lame questions many many times (even though you should use the forum search), and unlike most forums, you could end up with some lifelong friends. There are a few people here interested in squirting their rides so you are sure to generate a lot of enthusiasm if you post often and provide pictures of your project (or of half naked women).

I've done a bit of background reading on Microsquirt and am quite keen myself though too short of funds.  My strategy would be to do ignition first, then fuel.  I believe that Microsquirt will work pretty much out of the box for ignition triggering (wasted spark) on the longtooth TCI pickups.  No fiddling around with crazy toothed wheels, and it will drive the coils directly.  The ignition advance curve is published in the service manuals which is a great start.  However, I would only start on EFI after you had a known working bike to start from.

Check this out... the only attempt I know of to EFI an XZ http://hildstrom.com/projects/vision/index.html

[C Clement]

I guess I did ramble on a bit in the first post. My specific concern is the low compression. In my experience, I would expect the compression to be above 120 psi. I has to crank the bike quite a bit to get the rear cylinder up to 85 psi. While I have rebuilt several engines before, I was not planning on doing that with this bike and was hoping to spend most of my time and money on the Microsquirt conversion.

I am well aware of the joys of the Vision. When I was a senior in high school my uncle gave me a 1982 Vision for about 3 months. He was hoping to sell  it to me. I had great time on the bike a put a lot miles on it. However, I already had an Honda XL 500 and his $800 asking price, while more than fair, was money I needed for college in the fall. My brother ended up buying the bike so I got to spend a lot more time with it  over the next few years.

Thanks,

Craig

[The Prophet of Doom]

Seem low to me, and suspiciously different but have never tested cold engine.  Check your valve shims before you toss the bike - there's a special tool you will need, but you dont need the tool to diagnose.  Procedure in all of the service manuals and Haynes.

The specs are compression pressure (at sea level) on warm engine:
Standard: 980 kPa (10 kg/cm2, 142 psi)
Minimum: 882 kPa (9 kg/cm2, 128 psi)
Maximum: 1,079 kPa (11 kg/cm2,156 psi)

Difference between each cylinder:
Less than 98 kPa (1.0 kg/cm2, 14 psi)

A few dops of oil in each cyl will help diagnose ring issues if the pressure goes up

[C Clement]

Thanks for the responses. I guess I'll do a little more diagnostic work before giving up.

As far as having a warm engine to test that is tough when it won't start. As I mentioned, I did go through the carbs, the accelerator pump is working as I can see fuel spray when cranking on the throttle. The bike will cough a bit like it is thinking about starting. Both plugs fire out of the bike but I'll hook them up to the timing light as someone on the forum suggested in another thread to make sure they are firing in the cylinders.

I'll report back the results of that test as soon as I can get another free minute.

Thanks,

Craig

[Lucky]

clean carbs, Clean carbs, CLEAN carbs!!!

my wife's V was exactly the same, numbers close to that too.  it was dirty carbs.  dirty carbs are the root of all evil...  they will cause all sorts of symptoms on this bike that you would never believe are carb related....

[QBS]

Accellorator pump gas is a good sign.  Coughing is a good sign.  Coughing and not starting led me to think new plug caps and wires might make the plugs have an easier time firing.  Not knowing if the plugs, caps, and wires are good can make diagnosis impossible.

What you want is a big fat bright blue spark with a nice zap for extra points.  Anything less is suspect.

[C Clement]

Thanks for the replies. It looks like QBS was on the right track. I checked the wires and caps for the spark plugs and the cap on the front cylinder came right off. I screwed it back on to the wire and  was able to get the bike to fire on carb cleaner. I have gone through the carbs as I mentioned so I'll try them with the repaired wire. Maybe there is  hope yet for the old Vision. If I can get it to run on the carbs and the compression on the warm engine is ok I'll start trying to get it converted to fuel injection with the Microsquirt. Fuel injection should sure liven up the Vision.

Craig

[QBS]

Seems like Tiger used to sell plug wire sets.  But, I could be mistaken.

[pullshocks]

Don't give up Craig.  A viable fuel injection setup would be a most welcome development in the Vision world.

Clean electrical connections are right up there with clean carbs.  I struggled for months to get my Vision running right.  What put it over the hump was new plugs, caps, and wires, plus cleaning every electrical connection.  I wish I had done that much earlier in the process.

Another thing, the battery has to be really charged.  If you are cranking a lot, get out the jumper cables

[Tiger]

Seems like Tiger used to sell plug wire sets.  But, I could be mistaken.

8) You are correct Q... NEW,custom made to order and shipped to any location...A brand new set of spark plug wires/caps, ...only $25.00 + (actual) shipping 8)

               8) ....... TIGER ....... 8)

[C Clement]

Sorry for the long break without an update, work got crazy and I've not had any free time.  I found an old Suzuki in the local classified that has the old British twin look I've been wanting for a cafe project so that has taken up the little free time I get.  As a blatant bribe I told my 17 year old son that if he cleaned my shop he could have the Vision.  If you could see my shop you would know who got the short end of that deal.  He actually got it about half cleaned before the lure of the Vision sucked him in and he started working on it.  As any of you who have worked on projects with sons know, it is back to my project again as he works on it. 

The good news is his more careful cleaning of the carbs has got the bike running and it will rev with the choke on but any throttle with the choke off and it dies.  To my mind that indicates lean conditions in the carbs so we are trying to remedy that now, any suggestions are welcome.  I have told my son that he needs to order the CD with the manual before we get to much farther along as I hate working on these thing without so idea of how things go together.

Again, thanks for the encouragement and advice.

Craig

[QBS]

You're on the right track regarding thinking that the carbs are lean.  It's is probably the high speed fuel jets buried in the body of the carbs.  Getting the CD is the very best Next Move.  Cheers.