2000 GP1200R Rebuild

[bainer1290]

Got the motor pulled and disassembled. I am going to need to have 2 cylinders replated or to find 2 good used cylinders. Crank looks good all the bearings spin and feel good and I don't really see any damage. The rods all have zero vertical movement and the small end looks identical on all 3. I think this is the first time the engine has been apart, so that would say the crank has 230 hours on it. What do you think about the crank, should I be worried and send it away for a rebuild or should I run it since it appears good? Anything else I can check/test on it?

[Oleg Russia]

Hey. if the bearings do not make noise, then the crankshaft oil seals must be replaced.

[bainer1290]

For sure definitely going to put some new crank seals in as part of the rebuild. Is there anything else I should look at on the crank to help determine if its in good condition?

[bainer1290]

I'm starting to get parts together for the rebuild and was wondering on jetting, the engine will be:
Stock crank
ProX pistons
Milled or Aftermarket head 91 octane
Stock Pipe with D Plate and Jetworks valve
Riva Rideplate and Intake Grate
Stock Carbs with F/A's and accelerators disabled

Looking on the forum the best setup sounds to be:
125 Main jets 1-1/4 turn out on high speed adjusters
110 Pilot jets, 1 turn out on low speed adjusters.
1.5 Needle and Seat, 95 gram spring (Dull Silver) 42-45 avg. pop-off pressure


Does this jetting change if I am running at 3,000 feet of elevation?

Does the Mikuni Rebuild Kit MK-BN38/44 SPR include the 95g "dull silver" spring?

Anyone have a milled or aftermarket head they want to sell?

[jeffg426690]

Start at 1 1/2 on the highs. 95g spring does not come w the Mikuni kit. Rejetting and fa's go hand in hand, don't do one w/out the other.
Milled head 20-thousands will put you at 135-140 ish - good mid-range and plenty safe on pump gas. Should be able to get it done for $60-80 somewhere local

[bainer1290]

Thanks for that Jeff! Always good to start a little rich... if I got the heads shaved 20 thou the combustion chambers can remain as is they do not need to be cut? Do I just use the regular head gasket then? I have read of a few that remove 1 or 2 of the 3 layers but I don’t want to compromise the seal and longevity of the motor.

[Jonesyfxr]

I believe removing a layer or two is a cheap way of bumping up compression. I’ve done a similar trick on small block chevy’s.

[bainer1290]

That makes sense, but with milling 20 thousand off the heads gasket surface I would assume that would not be needed?

[Jonesyfxr]

That makes sense, but with milling 20 thousand off the heads gasket surface I would assume that would not be needed?

I am not sure how thick the layers are, but I do remember reading about this trick.

[Jonesyfxr]

http://greenhulk.net/forums/showthre...=210294&page=2