Pro's & cons of a powroll stroker crankshaft.

[All X's]

I am looking at a powroll crankshaft for my 86 350x and I've been hearing some bad comments about installing one and would like some input from people who have one. Specifically about the increaced torque (how much?) and the crank blowing up. Thanks.:hail:

[NOS_350X]

I dont trust any stroker or big bore bikes. Rarely are they reliable. The little gain in power isnt worth loosing your engien time and time again.

[250sx]

I think alot of the reliability issues may have to do with the fact that most people also install a big compression piston and overbore kit at the same time. I wouldn't go any higher than 10:1 or so for something I was going to ride much.

[All X's]

Have you guys owned a stroker ,what is it that (blows up?) when they do go.

[SWIGIN]

most places weld the crank so its hard to get them rebuilt..... plus iv seen them crack off the weld and then they are junk

powroll dont weld them and the way they do it seems to be the best.

my buddy built a 6mm 350x back in the 90s(powroll crank)and it lasted years of mx racing in a quad chassis and tons of play riding.

we ended up lossing track of the bike but i seen it run for at least 6-7 years.

as long as the compresion is kept around 10-10.5 they seem ok..... just not anyware near as long lasting as a stock crank

[SWIGIN]

Have you guys owned a stroker ,what is it that (blows up?) when they do go.


normaly the rod goes or the welded cranks break at the welds

[All X's]

How much extra go can i expect with a stroker? 10% 25%?

[SWIGIN]

no idea on numbers but a crank adds low end torque and a big bores like to scream ....normaly

[armyvet]

I personally would rather have a big bore instead.A stroker crank will give you more torque due to the increased mechanical advantage but it wont rev as fast,me i like snappy quick revving power,just look at all the new 4 strokes,they all have big bores and short strokes.Once i rebuild mine,im going with a 452 kit,stock stroke.

[SWIGIN]

one thing to remeber the new bikes also have super light pistons and rotating mass.


if you are big boreing a motor that already has way more bore then stroke it will rev slower and have killer top end


comparing a new 450 to a older motor is like comparing apples to oranges

[All X's]

Guess I'll have to learn the hard way and try the big bore and stroker-bigbore separately cause i can't get enough info here. Thanks anyway guys ,but some of us just HAVE to learn the hard way!

[Ed200X]

If you blow up a stroked Powroll motor that was built and assembled to their specs. Then you revved it beyond redline through about 10 gallons of gas continuously, and that being the case I'd bet it was some other non-Powroll part that initiated the explosion. It has been my personal racing experience that a Powroll Honda is far faster and incredibly, MORE reliable than a STOCKER. See my reply to Ricky15 200x about his piston choices. Go Powroll and never look back. I'm already putting together a plan to Powroll the mill in my 200X. But not 'til a few more flight hours on my trike to satisfy myself I have the ability to handle the expected increase. (Kinda like steppin' up from a 1970 oil-burning Civic with a ignition miss to a fresh built and tuned blown 454 '69 stingray if I remember rightly!) And.....No, I am in no way, shape, or form related to or involved with Powroll Performance except as a VERY satisfied repeat customer. Go For It!

[84honda200s]

ive herd great things about them. but on the other hand ive herd from allot of people that strokers arnt that great. nor do the benefits out weigh the down falls/risks. i looked into a stroker kit for about 3 months before deciding against it. i herd way to many bad things about stroking an atv engine.


so i decided to have it bored 3mm, 10.25:1 wisco, lighten flywheel, taller cam, and some extras. it runs pretty danm good and strong.

[NOS_350X]

Ed200x, You have had some good luck with them, Not very many have been as lucky as you. And because your lucky dosnet meen everyone gets the same product you get. I Dont like to go big on any engine becuase i can keep it in the stock bore/stroke and make it run better than the strokers.

[All X's]

:confused: Sorry NOS 350x But running (stock) has never been my style. How could i compete with my nephew's 400ex? Also there's too much confusion on the subject of horsepower increase so, learning by experience is the only choice!

[NOS_350X]

My X's are by no means "stock" Stock bore/stroke thats it.

If your trying to comptete with a 400ex with a 200x get a diffrent bike, it wont happen, Even with the bigbore/stroker.

My 350x hasnt found a 400ex that would even think about running with it. and its stock bore/stroke.

I can make a stock bore/stroke bike beat the strokers/bigbores so why do it? You go ahead and get that strokers and ill be here with my 350, Whopin ass.

[All X's]

My X's are by no means "stock" Stock bore/stroke thats it.

If your trying to comptete with a 400ex with a 200x get a diffrent bike, it wont happen, Even with the bigbore/stroker.

My 350x hasnt found a 400ex that would even think about running with it. and its stock bore/stroke.

I can make a stock bore/stroke bike beat the strokers/bigbores so why do it? You go ahead and get that strokers and ill be here with my 350, Whopin ass.
That's nice and all but if your not going to share information for hop up's. then i can really do without your negative input.:bitchfigh

[Rex Karz]

There was nothing negative in Nick's post. If You know Nick, You know that He is the most competitive guy around. Add in opinionated and you see that it doesn't come across well on the net. Besides, it's just one man's opinion. To say that you can't get the information that you want after hearing all these different experiences comes off a little ehhh... there are too many variables. What did Powroll say? If they can't give you a good enough answer, then yes, time for the hard road. But please share your experiences.

I think it is interesting how Powroll heats and shrinks their cranks. My main concern if I were doing this mod would be the reliability of my 20+ year old engine. I would want to start with a crate motor and go from there. Let Me know if You want to get one here in the states and have it sent to Powroll.

[MR ATC]

The reliability issue is more of operator error then it is product failure. most people do not relize the maintenance a high performance 4 stroke motor requires. Oil changes after every ride is a must. additionally I'd say 90% of all 350X owners overrev them. Also as Rex pointed out these motors are over 20yrs old. not the best canidate for adding more stress unless the entire motor is gone over.

You did not state what kind of power you wanted other then to be able to beat a 400ex. something any strong stock 350x motor will do. they both produce the same H.P. stock...27.

As far as modifying four strokes there is a basic formula/order of doing mods.

Pipe,
Carb,
Piston, (high comp, or big bore)
Cam,
Port,
Crank,

while you can do them out of this order you won't see the maximun benefits. It also depends on what type of power you want.

you can also lighten the flywheel for faster revs but you'll lose low end torque.
playing with the ignition timing is also an option.

in my opinion to modify a 350X to be a 400ex killer. i would stay away from a stroker crank and stick to smaller mods all around.

pipe, 36mm carb, wiseco 10.25:1 piston, a mid to top cam, and a mild port job.

[NOS_350X]

That's nice and all but if your not going to share information for hop up's. then i can really do without your negative input.:bitchfigh

Do a search or send me a pm, You can easely find everything ive done.

Im sorry you cant get a stock bike to go fast, but its :bs: that you get all :booty: hurt about it.

Mr atc worded things perty good. I dont agree with the order he put the mods, i do things in a bit diffrent order. But its perty close. :thumbsup:

IMO do Everything you can to an engine, If its still not fast enoguh for you then get a big bore/stroke. And if thats the case your probably better off just getting a biger/faster bike. I have just over $400 into my 350x engine. How much do you think your going to have into a stroker?

[All X's]

Thanks ,now we're getting somewhere!! On one of my 350x's i alreadey have the exhaust and wiseco 10.25 : 1 piston I guess carb & cam are next? And crank will be the last.

[MR ATC]

Another thing to consider when hopping up a 350X is the clutch. The stock springs are not up to the task of a modded motor. You can purchase H.D. springs from Barnett clutch. If your plates are old/worn you may want to consider replacing them as well. Honda plates are some of the best. Or you can get the complete Barnett kit.

[All X's]

I went EBC any good?

[MR ATC]

I went EBC any good?

EBC Springs are a little stronger then stock. Honda plates are better.

[NOS_350X]

Im using OE cluch. Before i built my engine i went through several clutches Since its been built i havent had to replace them at all. Due to the fact i have to shift much less With the extra power it can pull a higher gear better.. Where with the stock engine i would feather the clutch to stay in the power.