Super Jet raider motor in superjet

[mike b]

Im throwing a stock raider motor into a superjet. Im changing the exhaust from the raider's rounded exhaust pipe to the superjet square exhaust. Do I need to adjust the carbs for the different set up. That is what i was told and just wanted to double check. What would i do if so, change jets or just adjust the motor?

 

[mike b]

BUmp. Need help. any info or links appreciated!

 

[550/440]

You will need to lean out the carbs a bit, the SJ square stock pipe does not flow like the big chamber out of a Raider. Sorry, I don't have any specs.

 

[mike b]

You will need to lean out the carbs a bit, the SJ square stock pipe does not flow like the big chamber out of a Raider. Sorry, I don't have any specs.

I heard about having to change jets? Like new pop off and other things that are over my head...

 

[runninAmuck]

i just put a 62t motor from a wave venture in my square nose. rebuilt the carbs and found a 120 jet in one carb and 130 in the other and mine runs fine. your gonna need to fine tune it which takes a while on a trailer. stock exhaust will not fit a 62t cylinder. your gonna need to hone out the bolt holes on the exhaust manifold

 

[mike b]

i just put a 62t motor from a wave venture in my square nose. rebuilt the carbs and found a 120 jet in one carb and 130 in the other and mine runs fine. your gonna need to fine tune it which takes a while on a trailer. stock exhaust will not fit a 62t cylinder. your gonna need to hone out the bolt holes on the exhaust manifold

Yeah but the bolt holes is all that needs to be changed on the exhaust pipe correct?

 

[runninAmuck]

yes. but what head are you running ? if you have the 62t head the 701 exhaust bracket wont fit unless you modify it. im in the process of making my own bracket right now.

 

[mike b]

yes. but what head are you running ? if you have the 62t head the 701 exhaust bracket wont fit unless you modify it. im in the process of making my own bracket right now.

yeah i was just going to make a bracket. Seems pretty simple to make something keep the pipe in place

 

[Vumad]

I heard about having to change jets? Like new pop off and other things that are over my head...

They are not over your head. Simple stuff. Just buy a $50 popoff gauge and read the mikuni manual.

Tuning can be challenging, but setting the carb to a spec is easy. What actual specs you need I'm not sure. Just don't be afraid of it. Don't run it lean and you're fine.

 

[Matt_E]

i just put a 62t motor from a wave venture in my square nose. rebuilt the carbs and found a 120 jet in one carb and 130 in the other and mine runs fine. your gonna need to fine tune it which takes a while on a trailer. stock exhaust will not fit a 62t cylinder. your gonna need to hone out the bolt holes on the exhaust manifold

This is not a fluke, it is the stock configuration in the couch 760 engines. They also have staggered compression, so don't go thinking your motor needs a rebuild based on compression differences.
The steps for fitting a 760 motor into a SJ are pretty easy.

1. Make the exhaust fit. Use a 61X manifold and a 61X head so that the stock SJ exhaust will bolt up. In order to get the 61X exhaust manifold to bolt to the 760 cylinder, you need to either increase the bolt hole size in the manifold or you need to install time-certs or helicoils into the cylinder exhaust bolt holes. Reason: The 61X setup uses M8x1.25 bolts while the 760 setup uses M10x1.25 bolts. Fix it at either the manifold or the cylinder.
You might think about port-matching the exhaust manifold to the cylinder, as the cylinder ports will be a bit taller than the 61X manifold ports. You will also need to either cut a 61X exhaust manifold gasket to fit properly or use a 62T manifold.

2. Use the right electrics. There isn't anything wrong with using the 760 stator, flywheel, CDI - but you cannot mix and match 61X stator/flywheel/CDI with the 760 stator/flywheel/CDI.

3. Disable the oil pump. This is done by simply installing a 701 flywheel bolt and flywheel cover (without oil pump and blocked off)

4. Either leave the carb jetting the way it is or bring both mains to a 125.

 

[mike b]

This is not a fluke, it is the stock configuration in the couch 760 engines. They also have staggered compression, so don't go thinking your motor needs a rebuild based on compression differences.
The steps for fitting a 760 motor into a SJ are pretty easy.

1. Make the exhaust fit. Use a 61X manifold and a 61X head so that the stock SJ exhaust will bolt up. In order to get the 61X exhaust manifold to bolt to the 760 cylinder, you need to either increase the bolt hole size in the manifold or you need to install time-certs or helicoils into the cylinder exhaust bolt holes. Reason: The 61X setup uses M8x1.25 bolts while the 760 setup uses M10x1.25 bolts. Fix it at either the manifold or the cylinder.
You might think about port-matching the exhaust manifold to the cylinder, as the cylinder ports will be a bit taller than the 61X manifold ports. You will also need to either cut a 61X exhaust manifold gasket to fit properly or use a 62T manifold.

2. Use the right electrics. There isn't anything wrong with using the 760 stator, flywheel, CDI - but you cannot mix and match 61X stator/flywheel/CDI with the 760 stator/flywheel/CDI.

3. Disable the oil pump. This is done by simply installing a 701 flywheel bolt and flywheel cover (without oil pump and blocked off)

4. Either leave the carb jetting the way it is or bring both mains to a 125.

Thanks for the info. But i don't have a 760 motor. Its a 701, i just have seen 62T marks everywhere and can't find the 61x. Maybe im not looking in the right places? ha

 

[Matt_E]

Doesn't matter, same info applies.

 

[mike b]

Okay thanks. Its weird. The couch said its a 700. The crankcase said 62T and j700 or something. Carb mani, exhaust mani, and head all say 62T.

 

[Matt_E]

Yes, all 701's that were used in sitdowns are 62T setups. That's normal. The only exception to my knowledge was the 93-95 Waveblaster. The casting for the 701 62T cylinder and the 760 64U cylinder are (almost) identical.

What I wrote about the 760 ignition does not apply fully, by the way. You could mix & match parts from a 96+ SJ ignition system with the 701 62T system. But you cannot mix & match 90-95 SJ ignition components with 701 62T ignition parts.

 

[Vumad]

This is not a fluke, it is the stock configuration in the couch 760 engines. They also have staggered compression, so don't go thinking your motor needs a rebuild based on compression differences.
The steps for fitting a 760 motor into a SJ are pretty easy.

1. Make the exhaust fit. Use a 61X manifold and a 61X head so that the stock SJ exhaust will bolt up. In order to get the 61X exhaust manifold to bolt to the 760 cylinder, you need to either increase the bolt hole size in the manifold or you need to install time-certs or helicoils into the cylinder exhaust bolt holes. Reason: The 61X setup uses M8x1.25 bolts while the 760 setup uses M10x1.25 bolts. Fix it at either the manifold or the cylinder.
You might think about port-matching the exhaust manifold to the cylinder, as the cylinder ports will be a bit taller than the 61X manifold ports. You will also need to either cut a 61X exhaust manifold gasket to fit properly or use a 62T manifold.

2. Use the right electrics. There isn't anything wrong with using the 760 stator, flywheel, CDI - but you cannot mix and match 61X stator/flywheel/CDI with the 760 stator/flywheel/CDI.

3. Disable the oil pump. This is done by simply installing a 701 flywheel bolt and flywheel cover (without oil pump and blocked off)

4. Either leave the carb jetting the way it is or bring both mains to a 125.

Interesting info on the different jets. I don't want to derail the thread so I sent you a pm.

 

[mike b]

Interesting info on the different jets. I don't want to derail the thread so I sent you a pm.

Derail the thread all you want man. If you have questions on it im sure i would and or other people looking at the post

 

[Vumad]

Derail the thread all you want man. If you have questions on it im sure i would and or other people looking at the post

I'm in the process of tuning my Superjet. It is a full limited, stock motor with just about every bolt on available with stock carbs and airbox.

My rear cylinder seems to be running leaner than my front one. I am running 53 pop with 135/75 provided by jet maniac. He couldn't advise me further. My new jets showed up today but I won't be home from work until tomorrow. I now also have the options of 137.5 140 and 77.5

I have a traditional dual cooling set up with 2 8mm Ada pissers. I am going got change the front pisser back to the stock 3mm pisser to put more water through the back cylinder and the pipe.

I think 137.5/75 will end up being correct but your post in the linked thread has made me curious. Would it be possible I would need a different jet in my rear cylinder than my front, and if so, why?

Never tuned carbs with different jets or heard of it, but my rear cylinder is running just a tad leaner than my front.

See quote above for the pm

 

[beenen]

did you ever get this in a running Mike? send me a PM if you did. I cannot seem to find how to send a PM lol