103 Big Bore Kit

[dougmclellan]

My opinion only: No!

If you upgrade the heads with larger valves, port & polish, bump the compression, then you will see a performance gain vs money spent.

However, if the price is right, that might be a good place to start, especially with the right cam choice.

I have an 09 Ultra with the Kuryakin Storm (stage 1 kit) breather, fuel/air manager, headers and pipe. It's helped but I would like more so I too am looking at going the 103 route. Is there someone on the east coast you would reommend doing my heads.

 

[95bagger]

Good call on the complete kit, especially the clutch improvement.

If someone says they have 100 hp, ask them if they have a stock clutch. I don't think both of them are compatible. My stock clutch didn't make it passed the dyno work. My next stop was Primo-Rivera.:newsmile105:

uh, that is not necessarily so. The stock clutch is rated at 145 ft-lbs torque, I have 96000 miles on a 100hp bike and have no problems with the stock clutch. ORIGINAL stock clutch.... Of course, I do not burn out intentionally, and only wheelie occasionally....treated well and adjusted properly, a stock diaphragm clutch will take what you can give it up to 103 hp with no problem

By the way, we are talking about ported polished and decked heads, 95 ci, 570 gear drive, 1.9-1.6 intake and exhaust, wiseco 10:1 pistons, HPC coated pro pipe, s&s e carburetor with Davinci annular boost, Dyna 2000 ignition on radical curve, 101-103 dyno spec.

 

[Chopper]

I agree with you 100% bagger, I always even give the s/e heavy clutch spring to the customer in a bag if the kit comes with it, the stock clutch works so great I even left it in a 131'' jims upgrade I done and the bike has over 20,000 trouble free miles on it. The s/e performance clutch has it's place on the track, but not needed on the hwy unless you just want to build the muscles up in your left hand.

 

[roadhog381]

I'm thinging on doing the same thing you did but still a little on the fence about bang for the buck value.I have a 2007 Roadking and would like a little more get up a go. I was wondering how noticeable the increase is and are there any bad issues because of the change like dependablity.The 96 's put off alot of heat does that get worse ?Now that you had it done would you have changed anything. Thanks for the help

 

[eighty80]

A couple months ago, I got my Dyna upgraded with the Stage III 103 kit straight from the H-D Racing catalog. Fantastic results. 100HP at 5,500 RPM and above 100 torque from 3,000 to 5,000 RPM. Beside the bigger displacement, I had upgraded the air cleaner and replaced the exhaust for the Screaming Eagle exhaust (for the look not the performance).

Lovely.

R2KVET

Sounds good!! Was that the 259e cam?

 

[charlie54]

i am getting ready to buy a 2011 street glide and am going to up grade to a stage2 103 . i was wondering if i went with the stage3 if it will still be reliable.also stage 3 kits don't have warenty which i think if harley installs it it should be.