Originally Posted by omar1951

Is it possible to bump the motor size to 103" on a the engine in this model? The motor is counterbalanced, and I'm curious if that makes a difference because the motor isn't rubber-isolated. Would be using stock components.

Originally Posted by hattitude

Yes & no.....

The displacement of a V-twin engine is a combination of bore size and stroke.

To increase bore, you need only to add new cylinders and pistons. To increase the stroke, you need to split the cases, change piston rods and bore the cases. That entails a lot more work if you do it yourself and/or money if you pay to have it done...

Your 88" OEM engine can be increased to a 98" with a cylinder piston change... anything more will involve splitting the cases and changing the stroke.

Actually, both my springer and my 2000 FLHR are now at 95". Both were done when the bikes were about a year old, and both have 40-45K on the clock now. Just was looking to get a little more bang for the buck. I'll be hanging on to these 2 until they throw me in the hole. Both jobs were done at the dealer where I bought the bikes, and the cost was relatively reasonable. I'm sure the Road King could be done, as the motor is rubber-mounted. I was just afraid that because the springer motor is counterbalanced and hard-bolted to the frame that any motor vibration would affect the structure of the bike, motor, frame, etc. Anybody have this sort of work done to a counterbalanced motor? Any downside to the work?

If by "using stock components" you mean using HD Screamin' Eagle parts, a popular upgrade to the 88" engine is the SE 95" big bore kit. I added one to my 2003 Heritage, about 4 months after I bought it new back in 2003. I still have the bike and it still runs really well. The SE 95" big bore kit was a big seat-of-the-pants improvement, IMHO..

So, if you are going to do the work yourself, I would suggest the SE 95" Big Bore kit. Good performance improvement, and easy to do..

If you are going to have a shop do it, contact one of the various forum sponsors, tell them your performance goals, and listen to their recommendations...

Good luck with your mods...

PS- I see you're in New York, you may want to give Hillside Cycles a call.. they do excellent work..

PSS- "eighteight" and I were typing at the same time.. as you can see, we gave the same advice, albeit he types faster and doesn't ramble on like I do...

Originally Posted by omar1951

Actually, both my springer and my 2000 FLHR are now at 95". Both were done when the bikes were about a year old, and both have 40-45K on the clock now. Just was looking to get a little more bang for the buck. I'll be hanging on to these 2 until they throw me in the hole. Both jobs were done at the dealer where I bought the bikes, and the cost was relatively reasonable. I'm sure the Road King could be done, as the motor is rubber-mounted. I was just afraid that because the springer motor is counterbalanced and hard-bolted to the frame that any motor vibration would affect the structure of the bike, motor, frame, etc. Anybody have this sort of work done to a counterbalanced motor? Any downside to the work?

Originally Posted by hattitude

There was no downside to my 2003 Heritage softail when I added the SE 95" kit to its "B" engine, back in 2003. It's still running strong and very well...

If you want a little more bang for the buck, and you haven't addressed the spring cam tensioners yet.... When you open the cam chest to address the spring cam tensioners, you could add a new cam....

My 2003 Heritage ran well with the SE203 cams that came with the SE 95" big bore kit. When I addressed the spring cam tensioners, I added Andrews 26 cams. The bike does run better, but can't say it's a huge difference. Seat-of-the-pants it's similar... but it is better.. There are many cams to choose form should you go that route.. Just pick a cam that will move the power to the RPM band where you want the power most....