I would like to raise the gearing on my 82 XV-920 but I don't know if a larger sprocket will fit in the cases or a smaller one in the rear enclosure.  Has anyone done this?  Has anyone eliminated the enclosure and used 530 chain?  Did this allow for a larger front sprocket or only a smaller rear?  Where did you get the sprockets to fit front and rear?  What is the standard US gearing?  Is the TR1 geared higher for autobahn use?  Can I get the European sprockets from someone over there?  Any help appreciated.  Thanks.  Hope you like the picture of my bike in the Gallery section.   Peter  

 Peter
 I don't know what the standard US gearing is but the UK TR1 has a
 16 tooth front sprocket and a 35 tooth rear. as far as different  
 chain sizes go the front splines are unique to this motor and
 nobody in the UK has sprockets in anything but 630 the rear is no  
 problem for most suppliers though. I have already posted a message
 to find out about different size sprockets but no answer yet if
 you look at Sepps bikes in the gallery he uses a smaller chain
 the only way I can see changing the chain size is to grind down
 the original sprocket then turn out the centre of whatever size
 new sprocket and TIG weld the two together. hope this helps
 drop me a line if you have any luck
  Roy  

Roy, Thanks for the info. I learned from a US website that standard US gearing is apparently 16/35 too. My source indicated that perhaps a slightly smaller rear would fit.  I'm not ready for welded sprockets, but perhaps a 33 or 32 rear would be OK.  Any sources would be helpful.  PY  
   

I´ve got the info from the swedish TR1-club that the solution is to buy an universal rear sprocket and machine it to fit. There is no sprocket that fits right away. Apparantly there is no place for a bigger front sprocket.
I´m the proud owner of a TR1 from 1981 (1000cc).

I have removed the chain enclosure on my XV 920 as I have installed Yamaha XS 650 wire wheels on my bike (damn enclosure leaked anyway). My bike was recently pictured in the gallery and you can see it's naked chain. When I was a motorcycle mechanic many years ago, I would take notice of what parts were interchangeble on motorcycles. Many Yamaha parts are interchangable (i.e.: XV 920R and XS 650 rear sprocket bolt patterns are identicle, but the XS 650 chain is a 530). I was also a Kawasaki mechanic, and many Kawasaki parts are interchangable with Yamaha parts (sprockets, suspension, valve shims, and wheels). So I would suggest, taking your rear sprocket off and see if it matches the bolt pattern of a Z1, KZ 900, or KZ 1000 sprocket. I would not be surprised if it did match. There were many different diameters of those sprockets made as that bike was raced for many years in many different kinds of races. Good luck.

Update on alternate chains and sprockets:  Yamaha XS-650 twin rear sprockets will bolt right on to XV/TR1 hub.  These use 530 chain, but enclosure cannot be used and a spacer will have to be made to take the place of the spacer pressed into the outer part of the enclosure. XS 650 front sprocket has the same spline, but does not use the same mounting system on transmission output shaft. Does anyone know of another front sprocket with the same 6 point 24/30 mm spline which mounts like the XV/TR1 sprocket using a separate splined keeper and two hex-head bolts?  

Correction:  XV/TR1 transmission output shaft spline is 26/30 mm, 6 grooves, six lands approximately 4mm wide

Guys,
In regards to all the sprocket discussion, I changed my rear to a 33 tooth a couple of years ago.  The chain enclosure still works just fine.  I'm going off the top of my head (it's winter in Iowa) but I believe the rpm's dropped about 250 at highway speeds.  I contacted Sprocket Specialists (I believe in California) and they had no problem producing this sprocket.  I believe it was about $65.
Darian

Salut
habe ich Virago XV1000 Rahmen n°42J - * * * * tief in meiner Garage.  Der Motor wird gebrochen, und ich suche einen Motor oder einen niedrigen vernünftigen Preismotor mit den Papieren.  Entschuldigen Sie es für das Deutsche, es ist google, das trraduit vom Französischen am Deutschen.
Danke im voraus
Salut,
J'ai une Virago XV1000 chassis n°42J-**** au fond de mon garage. Le moteur est cassé et je cherche un moteur ou un bas moteur à prix raisonnable, avec les papiers.
Excuse-moi pour l'allemand, c'est google qui trraduit du français à l'allemand.
Merci d'avance

I'm looking for pilot screw for YAMAHA 920 or carburetor repair kit