RIVA Race Engine Advice

Location
Guam
I picked up a used motor from a friend and he told me it was an old Judge motor from 02.

-RIVA Ported and Epoxied Cases signed AK47
( They look to be decked as well)
-RIVA 61x Cylinder sleeved and marked 85.5
-R&D Flat Top Pistons (Comp is 220 psi)
-Hot Rods Crank
-Blowsion Girdled Head w/ custom cut domes
-RIVA intake w/ Spacer Plate
-VF 3 Reeds
-Dual 48mm NOVI's w/ external fuel pump.
-MSD Total Loss Ignition
-R&D Rev II Dry Pipe w/ water injection. (will be up for sale shortly, I plan on running a B Pipe)

This thing has low hours, and looked mint. I did fire it up before I got it and it sounded good, but comp was low on the pto cylinder. Anyway, after blowing the thing apart I found the culprit to be stuck rings. (Probably from this motor sitting so long) Now that everything is removed. I spun the crank and it sounds kind of weird. Also, there is a bunch of rust everywhere in the crankcase. Wrist pin and bearing was rusted and pitted on PTO cyl. Otherwise, inside this motor was clean including the cylinders, head, and domes.

I want to detune and run this motor in my B1, but don't want to blow it up. Could anyone take a listen and tell me if I'm okay to run this, or should I be looking for a rebuilt crank.

Thanks,

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Location
Guam
Do you guys think it will be worth keeping the total loss setup, or just run an msd enhancer? I will not be using this motor for a race setup, but more free-ride.
 
Location
Guam
Which total loss? Zimmy is looking for a good deal on a multi channel digital TL...

This is what I pulled out of the race ski with the motor. I might end up running it if I can't piece together a charging system to replace it. I also don't want to lose to much performance either, so I have to weigh it out. That's why I'm asking for some advice to help me go in the right direction.
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Sanoman

AbouttoKrash
Location
NE Tenn
l basically had the same set up years ago on a Judge/riva blaster.The ski was very reliable with never any issues.lf you start changing a bunch of stuff,it will never run at it's peak performance.That engine was set up to run as a total package.Either build it back to it's original form or flip another engine in it.
 
Location
Guam
l basically had the same set up years ago on a Judge/riva blaster.The ski was very reliable with never any issues.lf you start changing a bunch of stuff,it will never run at it's peak performance.That engine was set up to run as a total package.Either build it back to it's original form or flip another engine in it.

Thanks for the info.
I can't really get race gas out here, so I have to detune it some anyway. I'm pretty sure I can get it to be alright on the power. It know it won't be as strong as it was with 220 comp and race gas, but don't you think there will still be alot of useable power available with a lower comp, and charging ignition?
 

Big Kahuna

Administrator
Location
Tuscaloosa, AL
Lower compression and you should be ok, but keep in mind "Should" Compression is not just a factor in where it is safe to run race gas. Port timing plays alot into this. Contact ScottieMac here. He knows alot about Judge motors.
 

Pablo

sqeez bth levrs & lean bk
Site Supporter
Location
georgia
Pull some timin off with that TL and bring the compression down to sub-200 range. U know ur gonna be givin that blaster hell and running Wfo for decently long stretches so unless you have some race gas you better bring it down some, but I'm with Sano on it being a package. I'd keep the pipe, ignition, and engine together and lessen compression with new domes and either soften the TL settings or go to a MSD enhancer (or new ATP epic). I've never ridden a blaster with a hot engine and TL. I bet it would be fun!
 
Location
Guam
Thanks for the info guys its really helpful. I'm looking for some reliability, so if I can't get it out of this motor I might go in another direction. I definitely don't want to run the dry pipe with water injection in the sandy water I will be riding in, and my experience with race ported motors is very limited. I was hoping to add a spacer plate to the cylinder base to get down to 180 comp, and put is an msd enhancer or epic, but from what you guys are telling me it might not be a good idea.

Anyone want to trade for some Kawi Tripple stuff?
 

Half flip95

Formerly pondracer95
adding a spacer plate to the base gasket is a horrible way to lower compression. from what i have read i see only two possible ways for you to come out of this with your sanity and a reliable pump gas engine.
1. send the complete package to one of the many performance shops recommended on this site. tell the you want it set up as a reliable pump gas motor. you may need a re-sleeve / port to accomplish this
2. Sell it and build from scratch
 
Location
Guam
adding a spacer plate to the base gasket is a horrible way to lower compression. from what i have read i see only two possible ways for you to come out of this with your sanity and a reliable pump gas engine.
1. send the complete package to one of the many performance shops recommended on this site. tell the you want it set up as a reliable pump gas motor. you may need a re-sleeve / port to accomplish this
2. Sell it and build from scratch
That's pretty much what I'm looking at. I already have a stock 61x/62t motor to build up from, I was just hoping that this would be another good option for me. I have not been able to locate a Kawi 1100 here, so my next move will be Yamaha 1200 if I'm not happy with the power of the pump gas twin.

Anyway thanks, at least I can be excited about getting this done today!
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