Big Bore Kit

[TerryJLasVegas]

I'm considering buying an 03 Ultra and the seller is claiming that the bike has a big bore kit. It looks like a standard size motor to me. Is there an easy way to confirm if a motor has a big bore kit or not?

[secoleman57]

Well since bore size is rather difficult to tell by looking from the outside probably not

[TerryJLasVegas]

Yea...that's my problem. I was wondering if there was any kind of identification (or unique feature) on a big bore head that would help me confirm that is was what the seller said it was is all. I've looked it over pretty good but nothing jumped out at me.

[Rhino40]

The only way to convince yourself short of pulling the heads and measuring the piston, is with your right hand ..... give it a good twist, a well tuned 95 is night and day compared to a stock 88.

[secoleman57]

Well even that is not a good indication.

Bought a 1970 something 750-4 Honda when in the Navy, Knew it was a hot bike and had been modified but nothing really stood out until I went WOT one day and I couldn't shut it down. Turned out one of the carbs had the end missing off the metering needle and it caught on the seat holding all 4 carbs open.

When I went looking for parts I took the affected carb into a independent and the guy told me I was nuts running that set up on a 750 (or something like that). Further investigation showed it had a 900 cc big bore kit and highly modified heads.

If you've never been on one before you probably have nothing to reference it to. Only way to really know what you've got is open it up and look.

[misinlink]

Not without looking inside as stated.

Owner says?
Does he have any documentation? Who did the kit- what kit?

Trust your gut.

[OLDDEADEYE]

Wouldn't the jugs have a P/N on them if they weren't just hogged out?

[TerryJLasVegas]

Turns out the Big Bore kit includes new jugs and pistons but not new heads so it's not likely that it would look any different from the outside. I'll press for documentation and see how it goes. Thanks for all feedback.
Ride safe.

[ClassichHarley]

Vegas, ask to see the DYNO printout.