What are differences between 1982 and 1984 engines?

[maciekmz250]

Hi Everyone!

I'm just in that moment when decision has to be made. My original engine is built up to the bottom end, and the time is for cylinders/pistons and heads to be installed. But unfortunately previous owner left bike sitting with water in engine, some of it stayed in both cylinders, so the liners and valves are DISASTER :(. I've found a complete engine for reasonable money, in far better condition than mine ( stored in dry place). The only question I have is the engine model.
My bike is 1982 and the donor one is 1984. Are they much different? The only things I need are barrels,pistons and heads. Do you know about any cons for using donor's "organs"?

Matt

[The Prophet of Doom]

Your best bet would be to work through the parts lists for both.

[dingleberry]

Why not just bolt the other engine in?

[don_vanecek]

1984? Oh, you are in Europe where Yamaha sold them longer, well, I don't really think "internally" these engines were any different for all the years and models made.  Any changes between the years are all external, different pipes such as the US 83 model, carbs, again the US 83, so, that 84 engine should be a shoe in. 

I have an "English" version of a Cycle Mechanics issue-now I'm not home as I write this so could have names wrong, they did an issue on the Vision oh maybe 2002 where they sort of dig up old tests on bikes, and other then talking about the difference, all external, on the 83 US model, no mention of any engine changes in any of the years. Interesting name to the article, the Vision, "neither fish nor fowl" sort of a nice bike but not really the best at anything, I assume this expression means more to you guys and gals across the great pond.   

[Walt_M.]

Since it is Euro, the only question is whether it is the low power model, cams and carbs are different.

[maciekmz250]

Hi
Thank you for all replies. I've just checked engine code - 11U for both, so they are the same breed. Differences in power are related to carbs, so there won't be any troubles.
The donor was running 2 years ago before went upon storage shelf - smells lovely with that petrol/oil smell, turns smoothly, puffs nicely when TDC. I'll pick it up on thursday:-)
Why I will not bolt it in frame? First I'm not sure about any paperwork for engine (need to put it in DVLA forms), second - anyway I would strip it into bits before running...don't know what Ogres live inside, and I've the original engine bottom end already done with new bearings, so I do not see any point in spending money and time for it again.
The only activity will be focused on cyls, pistons and heads, I'll nick water pipes and their flanges and left side cover, for they look much better than other.

There will be some inerruption in bike works - expecting my new boy to be born tomorow...wish me luck:-)
See you soon

[Re-Vision]

Wow! A new boy, early congrats are in order, especially when your profile says you are nearly as old as Methuselah (943).  LOL  Best wishes for all.   BDC

[The Prophet of Doom]

Totally understandable about wanting to retain the original matching engine number. 

Yamaha used 11U serial numbers for different models; the low power version has an 11U serial number 11U-050101 or greater even though it is an 11V factory code.

I've not seen any documentation about early year vs late year 11U, but you might have to take care.  In other markets there were certainly changes between years.  For example the 28V model has a different cylinder part number than the 16R it replaced.

[Rick G]

Back in 2002 or 03 , I sent a set of vision cams to Humber , in Poland . He had a German low power version and wanted to in stall North American cams as part of his plan to up grade the power . When he got them he reported that they were identical to what he had. Either there is no difference in the cams OR he did not have the low power version.

[The Prophet of Doom]

There's a sheet of differences on the XZ550.de web site
According to that the cam differences are minor, and only on intake.  There are carb jetting differences also.

[jefferson]

On U.S. models there are some differences between the 2 years. The 82 had shorter cylinders and a thicker head gasket while the 83 had taller cylinders and thinner gasket. There was also supposed to be a different diameter on the crankshaft flywheels.

Jeff

[maciekmz250]

NEW ARRIVAL No. 2 ( see also New Arrival No.1 if you didn't yet  :) )

Meet the Donor ...no paperwork of course  ;)

[don_vanecek]

Jeff, really, I've never read any difference in the "engine" itself other then "externally", mostly the carbs on the 83, I've never heard the frames are any different, what your saying would seem to require differences in the frame on the casting for bolt holes, can you be more specific?

[maciekmz250]

Donor split  ;)
Front cylinder went without a slightest bang, piston pin easy, rings flexing
Rear cylinder - no pain, but head is stuck on barrel, must find out some way to separate them, piston as above

Both cylinders still have standard bore and honing marks clearly visible - probably low mileage
It seems like well spent 100 quids  ;D
Matt

[jefferson]

There are differences in the part numbers for the head gaskets between 82 and 83 and I would suspect different cyl part numbers as well. There is no reason for a frame change due to cyl length. Why do you think a frame would have to be different?

Jeff

[don_vanecek]

Well, I guess I am not sure then what you mean by cyl length. makes me think the cyl are taller, hench any bolts holes will not fit engines with shorter cyl length..?????? the stroke and bore did not change on these engines?

Perhaps we are not on the same wave length here....sorry maciek, don't mean to take over your thread. 

[jefferson]

The distance from the base gasket to the head gasket is the spec that changed. I don't know the exact difference, but I would say 10 to 20 thousands. There are no bolts that bolt the cylinders to the frame and that distance would be manufacturing tolerance anyway. The bore and stroke are the same for both years.

[maciekmz250]

Hi
Problem regarding 1982/84 engine discrepancies solved - just measured both engines in all important places and all parts are the same, so no worries anymore. Thank you for all help.

Matt

[tremalzo]

My bike is a 82 European model. Two years ago I had a leaking water pump seal. Changing the complete crankcase cover with a spare one seemed the easiest solution. After changing the crankcase covers it turned out the thermostat housing was not interchangeable. It didn't fit the crankcase cover which came from a 83 or 84 European model.

[91hondast1100]

I agree with the crankcase differences which I unfortunately discovered the hard way.  I have two 1982 US XZ550RJ's.  One in almost mint condition but scratched crankcase cover and the other on possible donor list.  Found a crankcase cover advertised on eBay as an 82 and purchased it.  It sat for about a year and was stripped, sanded and buffed to shining brilliance.  The bike was being cleaned and restored for a show that was in two days time.

Crankcase cover installation was about the last thing I had to do.  Crankcase cover was mounted and then when I installed the water pump cover suddenly something wasn't right.  You could hear the term "WTF" come out of my mouth as I noticed the front bolt hole had nothing under it.  No receiving hole for the bolt.  I removed the crankcase cover and compared it to the old one and sure enough they are very slightly different and if one looks inside the stamped numbers are different by the last digit.

I was lucky in that I had Vision number 2 to help donate the correct crankcase cover.  It was in ragged shape, not so much scratched but just weather worn.  I was able to remove, strip, sand and buff said cover to gleaming glory.  And yes, I made the show deadline.  I'll post more on that in future.

So why is there this small difference?  Does this have something to do with fairing clearances for the faired 83 model?

1982 donor showing correct fitting of bolt.



Incorrect crankcase cover in place showing the mismatch with no hole for the bolt to go into.