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[Snakebyte]

I'm planning a build either a 4.375 stroke or a 4.625, 117 or 124.
My riding habits are hard seems like I'm bouncing off the limiter at least 5 times every ride on my build now. I know from reading and my own knowledge that piston speed kills. However I'm looking for the HP number without losing the stock look to much, so I want to use my original cases. As far as a 4.25 bore well I here too many leaking stories and the possible cylinder stud failure. So I'm going with 4.125 bore.
This is in my Dyna 2009. My rev limit is going to be set at 6500.
Should I go to a longer stroke for the numbers on the dyno or there really isn't that much difference and 4.375 is ..ok?
I'm a numbers guy. I'm looking to see the highest in my cu.in. What ever I choose.
I hope I'm not to harsh here. This is how I feel. And since this is the third build in search for stock looking performance. I need to get things straight. I don't mind turning a wrench every so often to replace pistons and sleeves. Just don't want a catastrophic failure meaning block or piston slamming the head or loosing a valve.
 

[sadunbar]

I'm planning a build either a 4.375 stroke or a 4.625, 117 or 124.
My riding habits are hard seems like I'm bouncing off the limiter at least 5 times every ride on my build now. I know from reading and my own knowledge that piston speed kills. However I'm looking for the HP number without losing the stock look to much, so I want to use my original cases. As far as a 4.25 bore well I here too many leaking stories and the possible cylinder stud failure. So I'm going with 4.125 bore.
This is in my Dyna 2009. My rev limit is going to be set at 6500.
Should I go to a longer stroke for the numbers on the dyno or there really isn't that much difference and 4.375 is ..ok?
I'm a numbers guy. I'm looking to see the highest in my cu.in. What ever I choose.
I hope I'm not to harsh here. This is how I feel. And since this is the third build in search for stock looking performance. I need to get things straight. I don't mind turning a wrench every so often to replace pistons and sleeves. Just don't want a catastrophic failure meaning block or piston slamming the head or loosing a valve.
 

Shorter stroke will produce longevity over longer stroke.  But if your ultimate goal is power and you don't mind an occasional rebuild, don't let stroke limit you.  The primary wear items of longer stroke are pistons and cylinder bores, and you'll increase the load on your crankshaft.   Not likely you'd see a catastrophic failure due to stroke, just increased wear...

[GMR-PERFORMANCE]

I'm planning a build either a 4.375 stroke or a 4.625, 117 or 124.
My riding habits are hard seems like I'm bouncing off the limiter at least 5 times every ride on my build now. I know from reading and my own knowledge that piston speed kills. However I'm looking for the HP number without losing the stock look to much, so I want to use my original cases. As far as a 4.25 bore well I here too many leaking stories and the possible cylinder stud failure. So I'm going with 4.125 bore.
This is in my Dyna 2009. My rev limit is going to be set at 6500.
Should I go to a longer stroke for the numbers on the dyno or there really isn't that much difference and 4.375 is ..ok?
I'm a numbers guy. I'm looking to see the highest in my cu.in. What ever I choose.
I hope I'm not to harsh here. This is how I feel. And since this is the third build in search for stock looking performance. I need to get things straight. I don't mind turning a wrench every so often to replace pistons and sleeves. Just don't want a catastrophic failure meaning block or piston slamming the head or loosing a valve.
 

You have not given any real info on what you want other than you have lead us to believe there are a few  broken and you bang the rev limiter when you ride, and you want a braggging sheet with numbers. Hell every shop should jump to build you a engine..
 If you find this a bit harsh well it was meant to be. If you want real information take the time to write a real post, outlining what you have now and what you are looking to build use of bike, location or at least what fuel. EX system etc...  . I am sure if that is done you will get some helpful info. There are some builders on this site that I am sure would help you out. Good luck

[HILLSIDECYCLE.COM]

Pay little or no attention to that, but that said, a 4 5/8" stroke has been around since the mid-70's, and is really not considered a long stroke by any means.
That combined with a 4 1/8" piston brings you to a 124" which you knew.
Those engines can be a tame kitten, or a beast, or in between.
We have a client in Syracuse that had over 80,000 on his 124" last we knew, and still motoring along.
If you want power, and reliability, then a 124 is your man, at this point..................
Scott

[Snakebyte]

You have not given any real info on what you want other than you have lead us to believe there are a few  broken and you bang the rev limiter when you ride, and you want a braggging sheet with numbers. Hell every shop should jump to build you a engine..
 If you find this a bit harsh well it was meant to be. If you want real information take the time to write a real post, outlining what you have now and what you are looking to build use of bike, location or at least what fuel. EX system etc...  . I am sure if that is done you will get some helpful info. There are some builders on this site that I am sure would help you out. Good luck

 
I could have given more info, so here goes.
09 Dyna currently has 107 pistons, heads are corrected geometry, Baisley roller rockers with 1.94/1.6 valves CCP at 200. Thunder header exhaust. T-man sm660 cams. Current crank balanced, trued, welded, plugged honed rods and oversize bearings.
Over the past few months I have been gathering parts, so far I have Borezilla pipe loud baffle, and a set of 110 heads. I'll be shooting for about 205-210 CCP there is 93 available but usually run 91 with my current setup. I have gone as low as 89 and as long as I keep rims up it won't ping.
This bike will see an occasional 2 up long trip. But will see more solo riding. I like to go to dyno shootouts and have been known to make noise with some friends from time to time. 

[prodrag1320]

the 4.625 stroke isn't really considered a long stroke,wouldnt let it worry you at all.ide be more worried about bouncing it off the limiter on a regular basis.i would get a S&S lower end (or have your lower end done with a good rod set & Timken conversion) and set the rest of the motor to be reved that high on a regular basis,not a big deal,just make sure the motor is built for that purpose

[GMR-PERFORMANCE]

A 117 would allow the use of the crank that is already prepped. A correctly built 117 is nothing short of amazing. Add the 110 heads and if you like the t man cams look at the 662-2. We completed a rather mild 117 here not too long ago with the 662-2 and it went 135/135 with a zilla pipe 58 mm HPI t/b . Smaller heads than the 110. So with those heads set up you could have one heck of a ripper on your hands. I would suggest S&S cylinders for the 4.125 bore. Good luck

[HILLSIDECYCLE.COM]

A 124" is a big as what'll fit in the chassis....................at this point in time............

[Steve Cole]

A 124" is a big as what'll fit in the chassis....................at this point in time............

Maybe from S&S but isn't Jim's still offering there 131?

[Snakebyte]

the 4.625 stroke isn't really considered a long stroke,wouldnt let it worry you at all.ide be more worried about bouncing it off the limiter on a regular basis.i would get a S&S lower end (or have your lower end done with a good rod set & Timken conversion) and set the rest of the motor to be reved that high on a regular basis,not a big deal,just make sure the motor is built for that purpose

Are you talking about balancing the crank for the higher rpm?

I'm thinking of getting the SE 4.625 crank for the shorter rods. My thinking with it being a high compression around 210, for a street bike. The shorter stroke will not allow the piston to dwell too long at TDC.
Can someone tell me if the SE crank has races in the rods for the crank bearings?
Haven't looked at the S&S stuff yet.
I am sticking with flat tops so I might have to weld the chamber to get the compression that high. The weld will get my squish area up some too. I've used dome pistons before and it just seems like they or more prone to detonation then the flats. I'll also put the grooves in the head. I think I'm on the right track just going to be a slow process. The first two builds were hurry up and ride this one I'm takin a step back and thinking everything through.

[TorqueInc]

   You might want to consider finding a builder to lead you thru this.....no offense but you are all over the place.

[Snakebyte]

   You might want to consider finding a builder to lead you thru this.....no offense but you are all over the place.

It's your avatar. I seen it on another thread and my brains been rattled ever since. 

I don't think I'm that all over the place. I have questions that's it. I need to find info on the SE crank, so I asked. I'm asking to get all my information for the builder. If I don't know what I want then I'm stuck with whatever the builder thinks he wants for me....just asking questions and reading what I can on internet.

[TorqueInc]

 Ok I fixed the avatar

 The all over the place was this

   do you have a budget in mind ?

   do you have a shop in mind to do the work ?

 

[prodrag1320]

Are you talking about balancing the crank for the higher rpm?

I'm thinking of getting the SE 4.625 crank for the shorter rods. My thinking with it being a high compression around 210, for a street bike. The shorter stroke will not allow the piston to dwell too long at TDC.
Can someone tell me if the SE crank has races in the rods for the crank bearings?
Haven't looked at the S&S stuff yet.
I am sticking with flat tops so I might have to weld the chamber to get the compression that high. The weld will get my squish area up some too. I've used dome pistons before and it just seems like they or more prone to detonation then the flats. I'll also put the grooves in the head. I think I'm on the right track just going to be a slow process. The first two builds were hurry up and ride this one I'm takin a step back and thinking everything through.

S&S rods have races,dont think the SE do (we really don't use a lot of SE lower ends,pretty much all rebuilt stockers or S&S).what compression are your looking for & what CID and heads are you using? I would think youde be able to achive it by milling the heads.if not ide get domed pistons before I started welding up the heads.domed pistons wont cause any extra detonation if everything is set up right

[Rooster]

Maybe from S&S but isn't Jim's still offering there 131?

Yes, as well as a 135 now