MHR Mille pistons

If you need technical information or help with your late dry clutch Ducati S2, MHR 900 or Mille engine - post your FAQs, comments & questions here.
Kickaha
Diana
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MHR Mille pistons

Post by Kickaha »

Due to a dropped valve I will be after some pistons, a search on the net doesn't find to many available options

1) Are the 88mm kits for the 900cc engines the same?

2) Are the 88mm Pistons in the rubber band 750cc bikes the same?

I'm picking it wont be quite that easy, different deck heights etc

Image
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mizike77
860 GT / GTS
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Post by mizike77 »

That photo makes me cringe.....
79 Darmah
78 900 GTS
86 F1B
80 SSD
02 Harley FXD
72 H2 750 triple
08 KTM 300XC
there has yet to be a motorcycle line made that is as satisfying to ride, hear and look at as the ducati bevels
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Diana
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Post by Kickaha »

mizike77 wrote:That photo makes me cringe.....
It doesn't do much for me either
Image
Do you think I can fix it with a TIG :lol:
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rwhc80
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Post by rwhc80 »

Kickaha,

If Steve doesn't have them, try this



http://www.roadandrace.com.au/pistons.htm


Cheers
I have desmo disease, I just hope they never find a cure !!!
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Diana
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Post by Kickaha »

rwhc80 wrote:Kickaha,

If Steve doesn't have them, try this



http://www.roadandrace.com.au/pistons.htm


Cheers
ta I had looked their site but I must have missed that page

Had an interesting suggestion from two engineers who looked at the piston,they said "It's forged, weld it up and remachine it" think that might be a last resort :lol:
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Kickaha
Diana
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Post by Kickaha »

Turns out they seem to be in pretty short supply around the world (at least where I'm looking anyway) but road and race are just having a batch made by JE so I put my name down for a set, should be ready in 3-4 weeks
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rwhc80
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Post by rwhc80 »

Good news Kick,

Not keen on the idea of using a welded piston, so glad you opted for the new ones. "Not suggesting it wouldn't work" but for me, just doesn't sound the better of the 2 options.

Keep us informed on your progress ?????
I have desmo disease, I just hope they never find a cure !!!
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Diana
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Location: New Zealand

Post by Kickaha »

These arrived today courtesy of Phil from Road and Race

Image
Camera 002 by Kickaha13, on Flickr

I really want to just leave them on the table to stare at for a day or two :lol:
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rwhc80
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Post by rwhc80 »

Kick,

I know exactly how you feel, I got a set of 92mm JE's from Phil for my track bike about a year ago. Engine not yet competed, but I just pull them out every now and then to drool.

Almost seems a shame to hide them inside the engine !!!

Cheers
Rick
I have desmo disease, I just hope they never find a cure !!!
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Diana
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Joined: Tue Sep 02, 2008 1:14 am
Location: New Zealand

Post by Kickaha »

The engineer who is repairing the head rang today as he is final getting around to repairing it

It was actually the nut that holds the top bevel gears together that had come loose which lets the gears move and altered the valve timing which allowed piston to valve contact and the resulting damage
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Kickaha
Diana
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Post by Kickaha »

pretty slow progress due to a lack of funding but the head should be done in the next week or so

When my engine dropped a valve it damaged one cylinder slightly

The engineer doing some of the work has suggested fitting cast liners rather then replating as for less than the cost of replating one cylinder I can fit new liners to both of them

Anyone else have any thoughts on that one?
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wdietz186
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Post by wdietz186 »

They used cast sleeves up until the Mille with no problem. The only problem I can think of might be the OD of the sleeve might be too much for the cyl. barrel for a good fit and may interfere with the studs. I'd think at least 2mm min. thick for the spigot into the cases would be needed but it probably could be done.
rwhc80
750 GT
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Post by rwhc80 »

Hey Kick,

You may get a shock when you price a set of liners ! they are not cheap !!!

Explore the replate as an option !

Cheers
Rick
I have desmo disease, I just hope they never find a cure !!!
Kickaha
Diana
Posts: 51
Joined: Tue Sep 02, 2008 1:14 am
Location: New Zealand

Post by Kickaha »

rwhc80 wrote:Hey Kick,

You may get a shock when you price a set of liners ! they are not cheap !!!

Explore the replate as an option !

Cheers
Rick
I have an Ducati friendly engineer who can make the liners, the material isn't every expensive as we can buy "blanks" and machine to size

$562 to replate per barrel, I can get both liners done for the price of one barrel replate and still have change
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radecal
Parallel Twin
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Post by radecal »

Might find another problem going back to cast iron liners.
The Nickasil cylinders on the Mille required cast iron rings so you will have to source different rings to go with the cast iron liners.
I have only had to replace rings on my Mille as they wear and not the bore. You will have liners as well as rings wearing by going down the cast iron liner road. Cast iron rings for the Milles are available as the rings for the newer belt engines with the 88mm bore do the job (Mille part number superseded by belt number).
RAD
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