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Old TR1 Discussion Boards (read only) >> Discussion Board 2002 >> Upgrading of VX920 to the 1100
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Message started by Ortwin Verreydt(Guest) on 18.06.02 at 22:18:00

Title: Upgrading of VX920 to the 1100
Post by Ortwin Verreydt(Guest) on 18.06.02 at 22:18:00

Has anyone upgraded an 86' XV920 to the 1100 version?
I would like to keep the looks of the old style engine but increase the displacement to the 1100 version.
Has anyone done this before and can help me with some practical advise or,
does someone know of a specialist that can do it for me?
Thanks.


Title: Upgrading of VX920 to the 1100
Post by Thorsten (Canada)(Guest) on 19.06.02 at 04:49:00

Hi Ortwin, it's easy to increase displacement from 920 to 980 cc, as this only involves larger bore pistons.  However, the increase to 1100 cc involves a crankshaft with more stroke, which (I presume anyway) doesn't fit in the 920 crankcase.
Cheers,
Thorsten


Title: Upgrading of VX920 to the 1100
Post by Tomas Petterssson(Guest) on 21.06.02 at 08:20:00

Thorsten lies a little ,my machine TR1 is now 1200cc and it is bored from 95mm to 105mm and the same stroke as stock 69,2mm.
Tomas Pettersson
President of the Swedish TR1 / XV 750 Club
I don't like to write long letters, prefere to talk on the phone !


Title: Upgrading of VX920 to the 1100
Post by Lars Sandström(Guest) on 22.06.02 at 11:17:00

The crancase of XV-models 750-1100 is the same with the exeption of the final drive. The crancshaft of the XV1100 should fit the XV920 so if you cange cylinders and crancshaft you should get 1100 cc.
Best regards
Lars


Title: Upgrading of VX920 to the 1100
Post by Thorsten (Canada)(Guest) on 24.06.02 at 02:33:00

It's interesting that the 920 crank case will accept the 1100cc crank.  But wouldn't one have to use longer cylinders to make up for the greater stroke, and also longer cam chains?
Cheers,
Thorsten


Title: Upgrading of VX920 to the 1100
Post by Thorsten (Canada)(Guest) on 24.06.02 at 02:36:00

Hi Tomas, what pistons are you using, and did you have to re-sleeve the cylinders and bore the crankcase?
Cheers,
Thorsten


Title: Upgrading of VX920 to the 1100
Post by Tomas Pettersson(Guest) on 27.06.02 at 13:20:00






Title: Upgrading of VX920 to the 1100
Post by Chris Johnson(Guest) on 12.02.03 at 15:25:00

This was written by Lars Sandstrom:
"The crancase of XV-models 750-1100 is the same with the exeption of the final drive. The crancshaft of the XV1100 should fit the XV920 so if you cange cylinders and crancshaft you should get 1100 cc.
Best regards
Lars"
I want to put Virago 1100 crank and top end on my XV920RH.  The above "should fit" I would know if is "definitely will fit."  It would be very expensive for me to buy the `98 Virago 1100 engine I'm considering, only to have it not really fit.  I can do some machining, but don;t want a big design project because they do not really interchange.  The key question has to do with models.  I know the later 750 to 1100 are the same, the question really concerns the very early 920 (1981).
-Chris



Title: Upgrading of VX920 to the 1100
Post by Ortwin Verreydt(Guest) on 27.03.03 at 19:56:00

Thorsten, This is exactly what I am doing right now.
Basically use the TR1 pistons.
Next on my agenda is to replace the carburetors for a larger one.
But not as they are fitted today but a single carburetor with a single intake manifold to avoid the difficult alignment adjustments and to create a cleaner look.
This will be a "next winter job"