Head gasket
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My understanding is the head gaskets are the same and the crank cases are different suggesting there is more material in the H2R. I assume ( ass u me ) the compression ratio is lower on the H2R. Our H2 do develop more torque at low rpm that backs this up. This means that the H2 can never be full blown H2R spec. The only way forward is variable compression which means a 300cc could rev to 18k and be tractable for road use. I'm quite happy that this bike is RIDICULOUS as it is and does have the scope to give a reliable 250 -275 which apart from drag racing applications REALLY IS ENOUGH.
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That is also my understanding, although most of the press announcements did mention the gasket as one of the different parts, and so I would like to have a final answer, which means parts manuals
I have posted it before but this is DIRECT from Kawasaki's dealer site.
On the note of the head gaskets I had a thought today, the crank, pistons, rods head, gasket are all the same. The crankcases are not, I wonder if they had to raise the deck height to accommodate the larger camshafts to give a little more room for piston to valve clearance.
Below is a screen shot of the k-dealer site with the part numbers and what bike the gasket fits.
On the note of the head gaskets I had a thought today, the crank, pistons, rods head, gasket are all the same. The crankcases are not, I wonder if they had to raise the deck height to accommodate the larger camshafts to give a little more room for piston to valve clearance.
Below is a screen shot of the k-dealer site with the part numbers and what bike the gasket fits.
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Makes sense on two levels, firstly as you have stated the valve piston clearance. Secondly the lower compression ratio to allow more boost. By telling us this was achieved by a different head gasket suggests a bit of naughtiness on the part of Kawasaki , problem is what they have given is so rude anyway.
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Thank you Garth! This settles it once and for all.
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The difference in compression ratios between the two designs is very small. The R is 8.3:1 and the H2 is 8.5. From a performance standpoint it will not limit either engine. There are plenty of blown gas motors that run fine at 20 or 30 psi at 9 or 10:1 compression, so either bike's compression is not a limiting factor. I doubt if valve clearances are that close either, as I routinely find huge piston-valve clearances on stock bikes and I seriously doubt this will be any different. The R does have different cam specs with much more duration and probably more lift, but is easy enough to check if anyone decides to try R cams in their H2. I am still puzzled why they would use different crankcases when they could have just used a thicker head gasket or bigger valve pockets, there must be some other design difference in the cases besides just the deck height.
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Indeed, and in this case I have to admit I am rather annoyed that this is the case. They paraded the two engines to be identical but for very few parts, upgraded to handle the increased performance, but the crankcase is no small part, and it certainly was not what has been communicated to people, including the press.
Not that I care too much, but it is in fact quite gross misrepresentation.
Frio
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I came off a frequently used junction today and because I know the road surface is good and that there are no turnings onto that stretch of road I wound it on a bit. 10 mph to 40 mph in the click of the fingers then pop ktrc at 2 -2 kicks in as it starts to wheelie. LOOPY is my new best word to describe it as the old zx9r's were capable of loopy. And thats after three weeks when the first two were spent shaking my head in disbelief and the third week ridiculous seemed the best word.
The h2 and h2r have all the same rotating components like valve and springs and crank rods and piatons... The h2 and h2r does not have a base gasket as the cases are a "top case" configuration...
yes they have the same screens - they look like they are flame arrestors though.
The H2 and H2R also have the same velocity stacks as well as the same screens, same fuel injectors but different throttle bodies but most likely the H2R just doesn't have additional ports for emissions BS. The H2R also has a higher flowing fuel pump but same fuel pressure.
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Garth what are the cost differences between the 2 cases H2 and H2R. We know what the cam prices are, and head gaskets. To me the cases is the big question mark. I think the differences are for the extra clutch parts. Side by side will tell.
H2R:
Part Number 14001-0652
Description: SET-CRANKCASE
Package Quantity: 1
Item Status Code: Active
Contact Dealer Order Services
Price:
MSRP: $1,974.49
H2:
Part Number 14001-0651
Description: SET-CRANKCASE
Package Quantity: 1
Item Status Code: Active
Price:
MSRP: $1,974.49
Same price - note how you have to contact dealer order services for the H2r ;-)
Clutch baskets are the same inner and outer and pressure plate. Its all in the clutch plate stack, they have more plates to handle the power most likely as well as stiffer springs.
I wouldn't worry to much about the clutches though as you can increase spring pressure if needed.
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In looking at the H2 parts diagram, it is not difficult to put together a clutch stack with an extra plate. Various thickness options.
Is it confirmed that the springs are a different PN? Is the slipper mechanism the same? Sorry, not trying to make this your full-time job, but appreciate the help.
The clutch springs are same part number, same goes with the slipper mech.
The fibers are what seem to be "special" to the H2R the steels actually are the same part number for ninja 250/300's lol....
I'd shim the stock springs and see how it goes before trying to add plates. but that just me! I'm sur the extra plate will help with clutch life?
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Do you have access to the stack height info? I saw different thickness steels on the H2 fiche...some options.
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