760 Crank with 61x cylinders?

[EightySeven550]

Can you put a 61x cylinder on a 760 crank and crank case?

Would this give me more, less or same power then a 62t bottom end?

 

[Kennay]

same crank.... (650, 701, 760)


62t cases with a 760, so same thing exactly as the 701... the only variance would be one or two pulse line fittings for the carbs

 

[Mouthfulloflake]

yes

760 crank and crankcase is the same as used on the 701 dual carbed engines.

 

[BombThreat]

Are the 760 cases bored a little larger for bigger sleeves?

 

[Mouthfulloflake]

not sure, id have to go measure.

but its easy to open them up with a drill and a sanding drum.

Are the 760 cases bored a little larger for bigger sleeves?

 

[Kennay]

Are the 760 cases bored a little larger for bigger sleeves?

yea mon

 

[Matt_E]

Are the 760 cases bored a little larger for bigger sleeves?

Yes.
True 760 cases also have either two pulse fittings, or one fitting and a boss to drill a second one.

 

[#ZERO]

The base of a 760 sleeve measures 88.8mm and most of the later 62T cases with a single pulse fitting labbled 64V or 64U will work with the 64X cylinder.

 

[jules210]

could you do a 61x case/crank with 760 top end (from my understanding just open the case up for the sleeve)

would the crank and case be able to handle the 760 power especially if I plan on boring it out?

would this combo make some big smoke?

 

[Fx1 Love/SJ Love AZ]

The 760 motors are stamped 62t on the cases and the cylinders 62t as well as 64x, but the 760 will have 84mm pistons instead of 81mm.

These are my two 760 motors, one is in a blaster I just fixed for the guy I sold the RN I put the 760 from the really clear picture in. That clean 760 I pulled from a 97 wave raider 760 that ran is stamped 62t on cyl and cases.

 

[Fx1 Love/SJ Love AZ]

could you do a 61x case/crank with 760 top end (from my understanding just open the case up for the sleeve)

would the crank and case be able to handle the 760 power especially if I plan on boring it out?

would this combo make some big smoke?

I built this motor, my friend blew it up... Preformed it blew up, it was amazing. I had to have the 61x cases massaged a bit to fit the larger sleeved cylinder. That cyl is stamped 64x, and I had it bored .50 mm over. It had a single 46 and it hit like a ton of pricks for some reason. It blew because my buddy didn't know how to route cooling. That motor is getting rebuild now with 85mm pistons, and mild porting on the cylinder

 

[jules210]

I built this motor, my friend blew it up... Preformed it blew up, it was amazing. I had to have the 61x cases massaged a bit to fit the larger sleeved cylinder. That cyl is stamped 64x, and I had it bored .50 mm over. It had a single 46 and it hit like a ton of pricks for some reason. It blew because my buddy didn't know how to route cooling. That motor is getting rebuild now with 85mm pistons, and mild porting on the cylinder

was it a lot of work to get the sleeves to fit? how did you do it, is it a really precise job?

but the set up with a 61x case single carb stacked with 760 cylinders hits hard eh

 

[Fx1 Love/SJ Love AZ]

This is the motor when I took it apart, roached the crank even... So I have a new crank and bore with 85mm pistons needed. I want to know what the 62L is on my 61x bottom end haha. It's single carb as you can see but it's marked weird. All of the Yamaha engines I've had hit really hard.

 

[Fx1 Love/SJ Love AZ]

I had steve at action power sports do it, Steve Gold, he did an awesome job. Knowing that it was really just slowly dremeling the cases a bit till the cylinder nicely slid on, I would do it myself the second time. It as easy as doing a sport port on the cylinders. The only reason I did that motor combo was because I wanted single carb for cheap with more power. 62t is like $250 for a single carb mani. The r&d dual carb mani for 61x can be had for cheap, but the air flow supposedly isn't the same wich is by far correct. It's just a 760 though it can get plenty of flow. Put an aftermarket head for about 180psi and a bpipe, and you have yourself plenty of motor for any Yamaha hull. I ride an fx1 though and I enjoy my 701. I have the 760 as a plug and play setup on the side.

 

[Fx1 Love/SJ Love AZ]

That's the color the head turned from overheating, glad it didn't send a rod through the cases or something major, nothing too bad really happened even probably because the cylinders and cases are so strong.

 

[mike b]

I heard the electronics on the 760 motor are different. Any body able to add to that? I would assuming sticking the 760 on the 61x would be a decent motor but why not just bore out 61x cylinders to 84mm. 61x cylinder has better port timing does it not?

 

[Fx1 Love/SJ Love AZ]

They are totally different and weird even. But the motor has the rubber piece that you can take out to use 62t or 61x electronics. But I used 61x cases on that specific 760 I had as a spare motor so I used 61x electrics. The roundnose I built is a straight 760 with 760 electronics. They have a quick connect cdi that is weird but works the same. Has the same rev limit I believe it's just about making the motor capable of getting to that rev limiter. The blaster has the same motor as the RN pic 1 is the blaster 760 motor was pulled to clean and install a block off, 2 is the RN 760. You can see in pic one if you zoom into the flywheel, it has the rubber piece you can remove to use a 62t flywheel cover and electronics. You can see from both pics I'm using the 64x electronics cause why not!

 

[mike b]

Ill admit I thought of taking this motor out of my couch and running it in a standup but haven't done so yet. If its a true ripper maybe ill get a 62t 701 and swap over. Be something new at the very least!

 

[Fx1 Love/SJ Love AZ]

The hardest part with 760 into the blaster or the RN as a stock setup, is the pipe is a pain to mount. The 701 pipe to the 760. It is possible though, however just get a b pipe because it will make the motor not disappoint at all. Even with a stock pump

 

[Fx1 Love/SJ Love AZ]

It can be done on the cheap is all I'm saying. You can behave 61x or 62t cases laying around and pick up a 760 cyl on the cheap.