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On a ride
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Discussion Starter #1
Hey, when the '08's V-Rod's came with a bump in the displacement to 1250cc's, I thought there would be a factory option to go higher than 1250. While flipping through the pages of the P&A catalog I could find anything on this. Is Milwaukee offering a big bore kit for those wanting to bump 1130 or 1250 to something beyond?
 

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......My Title......
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I've never really looked into it much (being that I could never afford it anyway) all them guys over at the 1130 site would have a answer for you fast. I was also thinking with all the 1250 08's they would have to have something bigger for the screaming eagles, but from all I know they don't. I'm sure there is aftermarket stuff you can get. Bad thing about all the 08's having the 1250 it really makes the price of the used screaming eagle Vrods go down.
 

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On a ride
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Discussion Starter #3
Thanks lake... I think it is indeed the case, no bigger bore option from the factory. 1250cc's is it. Not that I have a need for more than what the 1130 can deliver. Just curious. Don't recall a model from Milwaukee ever not having a bigger displacement option from the factory. Plus, I've always heard all kinds of bigger bore potential exists with the Revolution engine.
 

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Just passing thru
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Yes there are big bore heads available. I have them sitting on my shelf in the garage because I couldnt pass up the deal, 329 to the door for the set thru Hales Harley Davidson on line.
 

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Yes there are big bore heads available. I have them sitting on my shelf in the garage because I couldnt pass up the deal, 329 to the door for the set thru Hales Harley Davidson on line.
The heads will do nothing for the size of the bore of the motor. They are just bolted on the cylinders to control airflow in and out of the motor.

The bore is going to be determined by the cylinders. There is only so much space to machine out before you start cutting into the water jackets.
 

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Just passing thru
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The heads will do nothing for the size of the bore of the motor. They are just bolted on the cylinders to control airflow in and out of the motor.

The bore is going to be determined by the cylinders. There is only so much space to machine out before you start cutting into the water jackets.
As you might be able to tell I am not a mechanic but I was told depending on which piston liner you use they will accommodate the big bore pistons.
 

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On a ride
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Discussion Starter #8
Turbo, Steve........
Ha! You first :)

Seriously, I thought I read back when the VRSCA was introduced all kinds of potential was built-in to the Revolution engine so series of displacement increases could me made for many years. So was mildly surprised when 1250cc became stock there was no option for something like a 1340cc V-Rod.
 

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BatRod
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It seems that going beyond 1250 creates interesting problems with long term reliability. 1340 seems to be a good reliable upper end. There are few (if any) 1550 motors running after a few thousand miles (I suppose something could be said about the abuse they receive). But Max has thousands of trouble free miles on his 1130 Turbo.
 

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BatRod
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Well, we just learned that Donald (OK VRod) went down last Friday when his 1430 locked up at speed. I stand by my previous post.
 

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This is an interesting discussion, and I've struggled with this decision for some time. I've heard of 1/4 inch strokers making moderate horsepower and being quite streetable. I've also heard that the 1/2 inch strokers are pushing the cases apart and spinning bearings.

I've also heard some folks say that 1/4 stroke is too much for a daily rider, and they are going with 1/8 stroke cranks (Destroyer cranks.)

I decided to hedge my bet and go with the HD 1250 setup and stroking it 1/4 inch to make a moderate 1350 motor. It should get somewhere between 140-150 HP with about 100-110 ft lbs of torque. It should be a 200k mile motor with regular maintenance, per the builder.

One thing is for sure, it's nice to have the options, and it's nice to have people pushing the edge of the envelope to find out where the failures occur. I know I couldn't bankroll the project.
 

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BatRod
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RJ, sounds like a great compromise. I think thats what Eagle had for their demo bike at Moroso a couple of years ago, that Ricky G rode around Okeechobee with us.
 

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I read where the stroker crankshafts were welded-up stock crankshafts. This might be the reason failures are happening often. Aftermarket needs to step up and manufacture new stroker crankshafts. But, there probably is not enough demand for that to happen. I think this motor needs more stroke. I am betting '09 will see more stroke now 1250's are standard.
 

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I read where the stroker crankshafts were welded-up stock crankshafts. This might be the reason failures are happening often. Aftermarket needs to step up and manufacture new stroker crankshafts. But, there probably is not enough demand for that to happen. I think this motor needs more stroke. I am betting '09 will see more stroke now 1250's are standard.
Not totally true. There are billet crankshafts to be had. The weld ups are cheaper to get, by $2-3K. That is why they are used so often. I don't think these cases can handle much more than 1/4" crank. The cases "walk" or separate when they take them to 1/2" and they end up spinning bearings, so I've heard.
 

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RJ, sounds like a great compromise. I think thats what Eagle had for their demo bike at Moroso a couple of years ago, that Ricky G rode around Okeechobee with us.
I think you're right. Get too greedy for HP and you end up paying for it. My pockets just ain't that deep.
 

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With my 1340/1320/80" Wiseco kit, the ext step will be a turbo, and then when th motor is worn, 1/8 stroke.
Or the other way around - first stroke then turbo since the bore is already in.

Keep in mind that stroking will always wear a motor faster than the same displacement increase with bore alone - piston speed and acceleration determine that.

How does that old saying go about no replacement than displacement for making power...its all about HOW the displacement is increased.

Also bearing in mind that stroking has a larger influence on the increase of torque than horsepower - and the converse is also true, that boring has a more predominant effect on horsepower than torque - hence a moderate increase in both will give a good compromise, and deliver a lot more reliability.
 

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BatRod
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Well, Ray Connor's 1430 gave it up at the Drag Strip in KC last Thursday at the rally. A crew of about 8 guys stripped it, on Video, at the party barn. Likely, the main bearings failed. Paul Diener thinks the crank was bad from the start. Eagle will put it back together.
 

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STAND AND FIGHT!
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Over the years, without really starting out with a preference, I wound up owning a couple of 350 Olds engined vehicles, and putting well over 150K miles on each. Compared to the ubiquitous 350 Chevy, the Olds has a short stroke. I had occasion to consider a significant difference between engines of similar displacement with different strokes. From this I predict that when comparing two engines that have similar displacement, and so similar fuel/air requirements, the stroked engine will get less fuel mileage because of significantly more travel in the bore, and so more cumulative friction. You wouldn't think it would make much difference, but I think in comparing the 2 V8s mathmatically, it added up to miles more ring travel in the bore per mile traveled on the road.
 

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HDF Oil Guy
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I read where the stroker crankshafts were welded-up stock crankshafts. This might be the reason failures are happening often. Aftermarket needs to step up and manufacture new stroker crankshafts. But, there probably is not enough demand for that to happen. I think this motor needs more stroke. I am betting '09 will see more stroke now 1250's are standard.
I do not think it is the weld-ups that need to be worried about. If you find a reputable company that knows what they are doing, a welded crank will have better results than a new one. A welded and stroked crank is gone over multiple times during the work process VS. say a Destoryer 1/8" crank that is punch out one after another on the line.

I will be using a welded 1/4" this winter in my homegrown 1350.
 
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