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So rumour has it the new 800cc Tiger engine is a bored out Daytona.
Has anyone else heard this and looked through the parts list, then done some measuring to see if we have a winner.
If the stroke is the same maybe all we need is a set of barrels and pistons to make the ultimate Daytona or Street.
 

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BOTM Marshall
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I don't think it will work.
from Cycle World, Feb 2011 issue
The longer-stroke crank throws would have run into the transmission mainshaft if fitment were attempted in the Daytona's cases, so the transmission shafts were moved a few millimeters--requiring a new crankcase casting and primary drive gears. The new cases, unlike those of the 675, also include a swingarm pivot mount.....
in the end, the 800 shares only 15 percent of its componets with the 675
 

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Aside from the fact that it would be a cool project, why exactly might you want a tiger engine in a Daytona? You would just end up doing a lot of wheelies and burn outs, I guess some people are into that kind of thing though...
 

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Why would you want to swap cams unless you mean to the Tiger from a Street or Daytona?
He wondering the Daytona/Street Triple cams will work in a Tiger motor....

I follow the logic it would make an 800cc Daytona.......certainly an interesting idea at least.
 

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Yes it would but just as important as left would be overlap. High torque low HP motors like the new 800 tend to have short duration [email protected] with a low overlap. With a set of came and adjustable sockets one would think you could certainly uncork this beast. Also maybe a thinner head gasket to bump up the compression.
 

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Agreed about overlap. Generally you see the short duration high overlap to increase low RPM scavenging, and the duration usually increases with the RPM band.

I don't have cam sheets for all three bikes to compare though, so its academic anyway:laugh:

I'd be more concerned with piston velocity, the 800cc motor is longer stroke than the 675s, so there could be issue with letting it spin to the Street's...and definitely the Daytona's higher redlines.

After that its a simple dynamic compression ratio calculation to see where you are at and what you need to do with cam timing.

IF the motor will mount to the 675 frame...and if the cam's are crossable.


Its an idea though. I would LOVE an 800cc Daytona...if for nothing else than shits and grins. :biggrinjester:
 

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I can all but guarantee that the motor will not mount in any other chasis. I was purely speculating about bumping the viewer output of the Tiger. As for piston speed I don't think there's any need to raise the rev limit as the peak power comes on well before redline as it is.
 

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' stroked' engines can generally get away with using more duration and overlap without milking the bottom end than a similar engine with less stroke.

Its all just speculation/ 'talk' for me, as I won't be messing with one.
 

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I read a detailed writeup of this new motor, and it's essentially a stroked version of the 675. But you can't just swap the crank, rods and pistons into a 675 motor.

The stroke is so much longer than the 675 that they had to modify the cases.

I'd like to see either motor side by side to be able to compare them.

It would be cool to have a writeup "tech" thread that shows the interchangeable parts, if any, like the head, cams, intake manifold, etc.

Homer
 
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