Archive for September 2011

XS650: Model, Year, Model code, Engine Number   Leave a comment

I made this list up some years ago. This version is arranged in Model Code numeric sequence. This code is found on the steering stem ID/VIN plate and Registration Papers. This is not necessarily the same as the first 3 places of the Engine Number.


XS-B            75-76                 533                        447-500101

I’m sure it’s not complete. May include errors. If you have a machine with a model code not listed here let me know.


… by model code – page 01


… model codes – page 02


Or here listed by Engine Number.

… by engine number – page 01


by engine number – page 02


As you can see, there are questions. (???)

… my original tables included these model code/engine number combinations … they are not however confirmed by Yamaha … if you have a machine covered by one of these please let me know and I will reinclude it in the above tables


Have a Model Code that’s not listed here? Let me know.

I wish to get an idea of production runs. The engine numbers in the above tables are arranged so … 447-300101 to (400000). I have the start number for each model. Yamaha have given the absolute end number-these are in brackets. Not necessarily the real end number. Where I know this I have entered it without brackets … 2F0-000101 to 006141. The information is from Yamaha Publication #12100-100E1.

I’m looking for approximate end numbers. If you want you could leave me your model and engine number. No Name. No address. When left in the comment box below no one will see it.


XS650: XS750 Service Bulletins   Leave a comment

I see someone was looking for M79-031. Service bulletin for XS750E and SE – shift mechanism adjustment.  For those who are interested, some time over the next wek or so I will post the Bulletins  for both twin, TX750 and triple XS750 models up to 81. Need a little time to sort them out and convert to jpeg or pdf.

Ok. Here we go. XS750 triple cylinder. 1976 – 1979. Became the XS850 for 1980-81.

  • ’76 XS750C
  • ’77 XS750D + 2D
  •  ’78 XS750E + SE
  • ’79 XS750F + SF

Look here for the Bulletins. Below is a list of contents …

  • M6-018A-1 … XS750D ’76 Service Data, 2 pages.
  • M6-018A-2 … Engine and Driveline Lubrication
  • M6-020 … XS750D Clutch Boss Nut Replacement
  • M6-030-1 … XS750D Special Tools
  • M6-030-2
  • M6-031-1 … XS750D Parts List Corrections
  • M6-031-2
  • M6-031-3
  • M6-031-4
  • M6-033 … XS750D Set-up Tuning for Best Performance
  • M6-036 … XS750D Installation of Instruments
  • M6-039A-1 … XS750D Driveline Cushion Modification
  • M6-039A-2
  • M6-039A-3
  • M6-039A-4
  • M6-043 … XS750D Front Wheel Set-up
  • M6-044-1 … XS500C/D and XS7850D Cylinder Seal Size and Selection
  • M6-044-2
  • M6-047-1 … XS500C and XS750D Eliminating Excessive Brake Drag
  • M6-047-2
  • M6-063-1 … XS750-2D Service Data
  • M6-063-2
  • M7-011 … XS750D, XS750-2D Special Tools
  • M7-013 … XS750D, XS750-2D Special Accessory Notice
  • M7-022 … XS750D, XS750-2D Oil Sump Modifications and Oil Quantity Changes
  • M7-023-1 … XS650D, XS750D, XS750-2D Changes to Splining of Transmission Gears and Axles
  • M7-023-2
  • M7-029 … XS750D, XS750-2D Driveline Modifications
  • M7-038A-1 … XS750E 1978 Service Data
  • M7-038A-2
  • M7-050 … XS750 Bearing Housing Modification
  • M7-051 … XS750-2D, XS750E Middle Drive Bearing Modification
  • M7-054-1 … XS750E Additional Pre-delivery Services
  • M7-054-2
  • M7-061 … XS750E Defective Rectifier/Regulator Unit
  • M7-073-1 … XS750E 1978 Service Data
  • M7-073-2
  • M7-074 … Shaft Drive Model: RearHub Lubrication XS750, XS1100
  • M
  • M  … I cant find the 1978 Bulletins – will post when found
  • M
  • M79-015-1 … XS750D, XS750-2D Float Pin Repair Kit
  • M79-015-2
  • M79-016-1 … XS750E, SE, F, SF Oil Consumption Diagnosis and Repair
  • M79-016-2
  • M79-016-3
  • M79-024-1 … XS400F, XS750F, SF, XS1100F, SF Conrod Numbering
  • M79-024-2
  • M79-030 … Multi-cylinder 4-strokes: Carb Synchronization
  • M79-031-1 … XS750E, SE Shift Mechanism Adjustment
  • M79-031-2
  • M80-022-1 … XS400, XS650, XS750 Factory Modification Campaign
  • M80-022-2
  • M80-022-3
  • M80-022-4
  • M80-022-5

Posted September 15, 2011 by xscafe in Manual - Service/Parts News

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XS650: OU/OW72 Heads   1 comment

Was discussing XS650 heads earlier. The major limitation to developing horsepower in our beloved engines (developing hp is a different topic to actually reliably and effectively getting it to the rear wheel).

Design limitations are found in exhaust port shape and cross sectional area-too large. Inlet ports could be smaller and would be better inclined downwards. The ‘Yamaha Racing Tips’ manual produced in 73 also recommends pocket porting-careful removal of material around the valve seats.


valve springs


The legendary dirt track battles between Yamaha and HD highlighted these limitations to the extent that for the ’76 season USYamaha brought in Tim Witham. The OW72 (I have seen these called OU72 and OW72-this would indicate 2 separate programmes-as far as I know this was a 1 off so I will, for continuity, use OW72) was developed. Didn’t stop the Harleys. Kenny Roberts lost the AMA Grand National Championship to Gary Scott. Time was short. Frames not properly set up. Shell Thuets eye for detail and reliability was missing too.

Still, from Roberts: ‘Best thing I ever rode’

Surprizingly Yamaha Japan had accepted Withams challenge to produce a new head. Probably as an R&D exercise for future 4 stroke engines. Kept King Kenny happy too. The head was cast totally different to the production ones. To accomodate the steeper valve angles ( racing: 56° production: 76° … inlet: OW72 – 43mm, prod’n – 41mm; exhaust: OW72 – 37mm, prod’n – 35mm) the heads were higher and the rockers shorter, enabling a lower rocker cover. Overall engine height was the same. Interchangeable with production motors.

The heads arrived from Japan in dribs and drabs. No ports, guides, valves, springs, cams. The engines had larger crankpins, improved pistons, rods,  gearboxes, clutches and deeper sumps. I can imagine the stress. Modern business practice could learn a thing or two from this about networked local sourcing for local consumption.



Racing combustion chambers were hemispherical, aluminiun, with steel valve seat inserts. Production heads had a steel cap cast into the alu and valve seats were cut directly into this.


inserts direct in alu head


XS1 heads showing the steel cap containing the combustion chamber … valve seats are cut directly into this


inlet port


exhaust port


Cycle World wrote an article about the development of these motors in their Aug 76 issue.

Original consensus is that 25 of these were produced. AMA homolugation rules required 1 complete bike and 24 engines and transmissions.

‘In order to be approved, a motorcycle must be a standard catalogued production model, one complete motorcycle produced, race ready, and at least 24 identical engines and transmissions must be available for inspection and purchase within the United States.’

There seems to be more (?). There is some confusion about this. It seems that Don Vesco produced some tuned heads back in the 70’s based on production heads and TRD valves. 650 Central sells your production heads CNC machined to tuner Lillies’ racing specs (these are your remanufactured production heads NOT ‘Yamaha’ racing heads).

70 hp motors appear to be relatively reliable. 75 hp motors not so.

I have seen several other attempts to address this problem, including homemade cast heads and machined billet heads. Of course, head modifications increasing available hp will expose shortcomings in other parts of the drive train, namely crankcases, crankshafts, clutches……………..How deep are your pockets?

Posted September 13, 2011 by xscafe in Frame - Design, Manaul - Literature, Manual - Other, Motor - Head

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XS650: Fucked up Political Brainlessness   Leave a comment

This link was posted here on All riders should take note. Looks like fucking dickhead european politicians are lining up motorcyclists. They’re not satisfied with ripping you off with the Euro. Stealing your future and that of your children and grandchildren by bailing out idiot economies and gangster banks isn’t enough for them either. That they are driving us into a war no reasonable citizen wants doesn’t bother them. After all their central banker overlords want this – it makes money – and the political bonus’s depend upon how far they can take it up the ass.

    • compulsory ABS,
    • the sealing of powertrains from the airbox, through the engine to the final drive (including the diameter and aspect ratio of the rear tyre),
    • restrictions on the aftermarket industry,
    • possible roadside checks by police or other government agencies to inspect emissions, detect owner ‘tuning’ and more.
    • France wants to ban bikes over 7 years old from urban areas for environmental reasons!

I could forgive them for targeting small gutless scooters and ring-a-ding 2 strokes.

I live in Germany. The powerhouse of europe. I am sick of my taxes being wasted by idiots who are only interested in lining their pockets and those of their masters. I love my ‘older than 7 year’ motorcycles and I want the Deutschmark back in my pocket.

I watched German tv last night. Paid for reporters telling me how much profit Germany has earned from the Euro. Sure, there have been profits. Have I seen any of it? Have you? What I see is my real income falling. My costs rising. Lower working conditions. Fear of losing your job. The ‘trickle down effect’ is in truth an upwards cascade. The top 1-2% earn massive bonus’s. Grand scale theft.

Sooner or later the German taxpayer will snap. Guillotines are easy to build. And, I imagine, very satisfying.


25th Sept -Action Now! EU Hands Off Biking!



A raft of issues emanating from Europe will have a profound effect on riders and the motorcycle industry generally. We must stand up and be heard. Some of these are driven by the EU Commission, like the new Type Approval and Market Surveillance Regulation that will see the introduction of compulsory ABS, the sealing of powertrains from the airbox, through the engine to the final drive (including the diameter and aspect ratio of the rear tyre), restrictions on the aftermarket industry, possible roadside checks by police or other government agencies to inspect emissions, detect owner ‘tuning’ and more.

There’s EU-funded development of electronics to control and govern speeds through warning systems or, ultimately, actual throttle control.

Ireland plans compulsory, full sleeve day-glo jackets for riders and pillions, France is debating compulsory reflective/day-glo clothing. Will UK insurance companies start saying that because we weren’t dressed in day-glo it’s our own fault that an inattentive driver drove into us? MAG says the onus should not be on the victim.

France also wants to ban bikes over 7 years old from urban areas for environmental reasons! Their congestion is already terrible and putting more riders into cars that pollute terribly when they are stationary, is bonkers.

Bikes are part of the urban transport solution, not problem.

Enough! There will be a vote by the MEP committee discussing the above Regulation in the autumn. We need them to listen. They’re meant to represent us. MAG and many others in the motorcycle community are negotiating hard with our own Government and our European representatives, but in the meantime….

Fancy joining 100,000+ French angry bikers from the UK? Here is how and when…

Fédération Française des Motards en Colère (FFMC – French Federation of Angry Bikers)




Excuse me now, I have such a knot in my stomach I gotta go puke.

Posted September 9, 2011 by xscafe in General, Uncategorized

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XS650: 77 Service News   Leave a comment

General and XS650 specific bulletins from 1977.

Gearbox splines, EPA.

M7-008 … general set-up check list

M7-014 … 77 XS650D technical publications

M7-017-1 … handlebar switch knob replacements 76 77

M7-017-2 …handlebar switch knob replacements 76 77

M7-019 … 77 engine/frame numbers

M7-023-1 … changes to splining of transmission gears and axles

M7-023-2 … changes to splining of transmission gears and axles

M7-030 … DID50HDS drive chain and master link

M7-033 … cam shaft sprocket systems

M7-042 … XS650E 78 service data

M7-052-1 … drive chain and master link

M7-052-2 … master chain and link

M7-067 … dealer setup and predelivery check list

M7-069-1 … introduction to EPA

M7-069-2 … introduction to EPA

M7-069-3 … introduction to EPA

M7-070 … 78 XS650E engine / frame numbers

M7-071 … XS650SE 78 service data

M7-075-1 … new battery service and maintenance

M7-075-2 … new battery service and maintenance

Posted September 2, 2011 by xscafe in Manual - Service/Parts News

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XS650: 76 Service News   Leave a comment

Wasn’t really a lot happening back then. Still, I’ve pulled these out of the collection. Specifically XS650 and general Yamaha related.

M6-005-2 … XS650C Technical publications

M6-025-1 … interchangeability of tachos/speedometers

M6-025-2 … interchangeability of tachos/speedos

M6-028 … headlight damper and collar … general

M6-040 … cylinder head cover (tappet inspection)

M6-045-1 … XS650D parts list corrections

M6-045-2 … XS650D parts list corrections

M6-045-3 … XS650D parts list corrections

M6-052 … XS650D service data

Posted September 2, 2011 by xscafe in Manual - Service/Parts News

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XS650: Patches   Leave a comment

My wife reckons I’m entering my second childhood. Secretly I know I never left the first. Life has been one endless playtime. Maybe I’ve just been lucky. I’ve been paid to travel the world and work in many different places and countries. Until I got married (at over 40 years old) I’d never stayed in one place for more than 2 years since I was 17.

I belong to the Australian XS650 Club. When you join you are given a club t-shirt and a small sew on patch.

sew on club patch ca 85mm dia and t-shirt front logo


club t-shirt rear logo


If you’re caught on a club outing or as a club representative without one of these you have the choice, beers all round or the naked dash.

To cut a short story long, I went to the 40th birthday celebration of our beloved XS650 a couple of years ago. Of course, I wore my t-shirt and made the effort of sewing the patch onto one of my vests.

I had found one of these on ebay too. So it got sewn on as well.


engine patch ca 100mm dia


At the event I was kindly given one of these from the Wuppertal/Ruhr Stammtisch, the event organisers.


Wupper Ruhr Stammtisch patch ca 90mm wide


Since then I have gathered several others.

Nederland XS650 Club.


Netherlands XS650 Club patch ca 85mm dia


 Danish XS650 Club.


Danish XS650 Club patch ca 85mm dia


 XS Racing Club, France.


XS Racing Club, France ca 60 x 40mm


And from Lowbrow Customs these 2.



Lowbrow Customs ca 75mm long


Lowbrow Customs ca 85mm wide…I contacted them asking if they would make a matching patch from the lhs…a definite NO!


And of course this take-off.




And this oldie from way back.

rather large.. ca 200 x 120mm … apparently also available in a smaller size too


from the heady 70’s … there is also a bigger one – around 7″

I have some other XS650 related patches somewhere. No photo yet.

Also some other generic Yamaha patches etc that I have sewn onto my vest as well.


vest – front


vest – rear


This project isn’t finished yet. As you can probably see. Funny thing is, since I started sewing these things on after the XS650 40th Birthday Bash I’ve never worn it. My son does. Under my protest.

If anyone is interested the vest is from Carhartt. US brand work clothing I was using in the Yukon. Pretty warm.

If you know of any other patches let me know. Or send me one.

Posted September 1, 2011 by xscafe in Forums, Frame - Design, XS Pics

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