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I have to split the case on my Banshee and will do so probley today. Tranny took a serious shit cant wait to see the mess in there. But on the better side hey the motor is out and thinking about steping it up a bit. Right now I have this combo

 

02 Banshee

bored .040

Basic trail/dune port by Eric Gorr

Stock Carbs 330 mains K&N Filter

T5 pipes and Silencers

Boyseen dual stage replacement reeds.

Noss cool head not yet installed - Tranny is broken dont need a head mod yet lol.

 

 

I know its not much haha but its alot better than stock.

 

Thinking about either doing a big bore 68mm cub motor with 35mm carbs and vforce reeds.

I would like to do a 4mm motor stroker but thats a stretch on the money and I could just have my stock crank trued and welded and I guess it would be best to replace the rods.... The cub cylinders would basically just be stock out of the box but I would do the clean up on the castings. No porting just clean up all the ports and entrances with a cartridge roll or something of that sort. I would like to keep this a pump gas motor and just change the domes to whatever needed in my cool head.

 

So what I am asking is would a stock stroke big bore cub with new carbs, and reeds blow my socks off compared to what I have now. Just looking for opinions. As of now my bike is a bit but not alot faster than buddys stock yfz450 Yamaha. Would like to just smoke him especially after he puts his new CT Racing pipe on. Let me know what you guys think. I appreciate all comments and suggestions. Thanks alot guys.

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I have to split the case on my Banshee and will do so probley today. Tranny took a serious shit cant wait to see the mess in there. But on the better side hey the motor is out and thinking about steping it up a bit. Right now I have this combo

 

02 Banshee

bored .040

Basic trail/dune port by Eric Gorr

Stock Carbs 330 mains K&N Filter

T5 pipes and Silencers

Boyseen dual stage replacement reeds.

Noss cool head not yet installed - Tranny is broken dont need a head mod yet lol.

I know its not much haha but its alot better than stock.

 

Thinking about either doing a big bore 68mm cub motor with 35mm carbs and vforce reeds.

I would like to do a 4mm motor stroker but thats a stretch on the money and I could just have my stock crank trued and welded and I guess it would be best to replace the rods.... The cub cylinders would basically just be stock out of the box but I would do the clean up on the castings. No porting just clean up all the ports and entrances with a cartridge roll or something of that sort. I would like to keep this a pump gas motor and just change the domes to whatever needed in my cool head.

 

So what I am asking is would a stock stroke big bore cub with new carbs, and reeds blow my socks off compared to what I have now. Just looking for opinions. As of now my bike is a bit but not alot faster than buddys stock yfz450 Yamaha. Would like to just smoke him especially after he puts his new CT Racing pipe on. Let me know what you guys think. I appreciate all comments and suggestions. Thanks alot guys.

 

 

HELL YES!!!!! As long as you get it to hook and keep the front end down. :headbang:

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HELL YES!!!!! As long as you get it to hook and keep the front end down. :headbang:

 

 

Sweet that is what I am looking to hear haha. So from you sig your bike it still the stock stroke also huh. How is the powerband for trail riding and such. I am confident I can pretty much tame most bikes into doing what I want them to do just wondering what its going to be like though.

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Sweet that is what I am looking to hear haha. So from you sig your bike it still the stock stroke also huh. How is the powerband for trail riding and such. I am confident I can pretty much tame most bikes into doing what I want them to do just wondering what its going to be like though.

 

 

For wide open trails, it's a blast. If you have to start and stop and turn and all that, it sucks. and yeah, mine's stock stroke. In the sand w/paddles I can spot my mildly modded YFZ a ridiculous number of bike lengths in 300 ft or longer.

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If you stroke it though, it gives a better angle for the Rods, crank and pistons so it has less stress on the motor. The shorter the stroke the tighter the angle will be and puts more stress on the internals. Stroking will also make the motor that much more reliable, and give more power. Just somethin' to think about.............. :beer:

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Hold on a second there...I think you're confused.

 

A stroked crank without longer rods puts more stress, the longer rods are better and they cut down the angle.

 

As long as your crank is in good shape, have it welded and new bearings put in to save your money.

 

It'll cost you around 550 or so for a good welded, stroked long rod crank and a heavy duty bearing for it. Any builder worth their salt will tell you the factory welds on a wiseco (hot rod) crank aren't very good, and they will reweld it for you, normally at a nominal charge.

 

Keep in mind, GORR cylinders are fantastic...you could easily get a few hundred bucks for them as long as they're not wasted and to far along the bore chain (.060 or more...)

 

I got 325 for my virgin stock port, stock bore cylinders and crank, I think.... With Gore Porting you could probably fetch upwards of 250 or 300 for the jugs alone.

 

Just a thought....

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What about running a longer rod on the stock crank. Isnt that how the 370 long rod motor is built. Just bored out to 66mm and longer rods on the stock crank? Would this be an advantage on a 68mm cub with stock stroke. I am also hoping my T5 pipes will help compliment all the different riding styles I do instead of just running a straight drag pipe. I know I cant have everything so as long as it runs good on the trails and good in the sand I'll be happy. We do some haulin ass trail riding though lol.

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Keep your stock cylinders and get a strong dune port, you'll be much happier. Trust me on that one...I've been there with a cub, T5 pipes and stock carbs.

 

You'll be running drag port timed cylinder with trail pipes....

You can get a much more user friendly port job and save your money for cubs.

 

If you rode 70% dunes and 30% fast wide open trails, then...I'd consider it.

I was just in your boat...I thought I could detune the nature of the cubs a bit. Wrong idea.

 

You'd be better off with a good port on your stockers.

 

The crank is offset 2mm (4mm total) and the rod is 5mm longer on a 4 mil longrod crank.

(I think it's a 115mm rod, not 100% on that one)...

If you got a stroker crank and dune port job to match, you'd be in good shape...

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I think my port job is mostly just a clean up on everything. I still have good compression with the stock head after the port job so I dont think the ports were raised much. Maybe i'll just send my cylinders off to Jim at Passion racing and let him do one of his 12 port jobs and the spend my money on a 4mm stroker kit with long rods. Sound like a better idea for all around way more power.

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Jim does a fine job, as does Jeff.

It would be wise for you to call both, get a feel for 'em...and make your decision.

 

Also...keep in mind, I'd ask them how backlogged they are... You might want to wait till off season when they're not as busy...and you have more time.

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Jim does a fine job, as does Jeff.

It would be wise for you to call both, get a feel for 'em...and make your decision.

 

Also...keep in mind, I'd ask them how backlogged they are... You might want to wait till off season when they're not as busy...and you have more time.

 

I have a 421 cub im selling

4mm stroke 68mm bore

standard trans (non override)

hinson basket with stright cut gears.

eletrics included.

90hp on gas motor

complete minus carbs /pipes.

first 2800 takes it (thats the shipped price)

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Keep your stock cylinders and get a strong dune port, you'll be much happier. Trust me on that one...I've been there with a cub, T5 pipes and stock carbs.

 

You'll be running drag port timed cylinder with trail pipes....

You can get a much more user friendly port job and save your money for cubs.

 

If you rode 70% dunes and 30% fast wide open trails, then...I'd consider it.

I was just in your boat...I thought I could detune the nature of the cubs a bit. Wrong idea.

 

You'd be better off with a good port on your stockers.

 

The crank is offset 2mm (4mm total) and the rod is 5mm longer on a 4 mil longrod crank.

(I think it's a 115mm rod, not 100% on that one)...

If you got a stroker crank and dune port job to match, you'd be in good shape...

 

I second that one! When I first built my cub I couldn't find any good pipes so I ran it with T5 pipes and my 33's. Yeah, it was an animal but it was like making that thing try and exhale through a straw. I finially got the CPI's and it woke that beast up.

 

If you expect to do any kinda trails you should really consider ported stock cylinders because the cub will just have too much of the wrong kinda power for trails. Yeah, you can ride it on trails if you are good, but you will be doing nothing but riding the clutch, on and off the gas, hitting your brakes every time it gets in the powerband. Cubs hit like a freight train all at once, not really good for trails. They are great for the dunes though, but even still I would prefer something with powervalves for just recreational riding.

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I talked to Jeff Today at F.A.S.T racing. Going to be sending my engine to him next week for some more extensive porting, 4mm long rod stroker, 35mm carbs and some other goodies. Jeff is the most helpful person I've talked to on the phone yet definatly give him a call if your thinking of major engine mods. Will let you guys know how it all turns out.

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