May be a dumb ? but big bore?

[BikerJim44]

Ok, I haven't done a 96' to 103 bb build as yet but I keep seeing that with the TC 95" jugs and different pistons you get the 103" as they are able to be used on a 96" TC. So with that said then can you just change the pistons on a 96" and make it a 103 without having to change the jugs or do much more than a light hone? Am I missing something here? Thanks in advance and No Max, I aint drinkin' or smokin' anything. LOL Spidey.

[rigidthumper]

103=96 + 3.875 bore & pistons
95=88 + 3.875 bore & pistons

[BikerJim44]

Rigid, so if I read this correctly then all that needs to be done is the original jugs bored to 3.875? Will the torque plates I have for the TC 88-95 then work with the 96" jugs? I have a machinst with boring bar who will do them up for me and I have the torque plates. Thanks. Spidey.

[Dennis The Menace]

Jim, the 95 and 103 kit pistons and jugs are same.  The diff from 88 to 96 stock motor is the stroke length--same piston and jug on both motors stock.

So, if you have a 95 kit, and want to install it on a 96, you will end up with a 103.

Disclaimer: This assumes that you have flat tops and stock heads and valves and valvetrain.  If you start messing with the pushrod lengths and cams and head gaskets and rocker arms, then you will need to be careful about the piston-valve clearancing.  At least, this is what a motor builder told me.

menace

[rigidthumper]

Yes, but- the CH on 103 pistons are different from 95 pistons. As long as the right pistons are used, the cyls are interchangeable.

[BONERACIN]

I thought the pistons where different?  Pin placement.

[BONERACIN]

Thumper, posted before i had i chance..

[bigfoot5x]

The cylinders are the same but the pistons are not. There is a difference between the 103" pistons and the 95" pistons. In both situations, the cylinders have to be bored out for the new pistons. The only reason I can come up with for HD always selling cylinders with pistons in their kits is to save mechanics time when doing the conversion. It takes about a week to get cylinders bored (at least around here) so the bike is apart and nothing can be done on it. If new cylinders are bought, the mechanic takes it apart and immediately begins putting it back together.

[Coff 06]

The pistons for the 96" are "stroker" pistons with different pin placement than the 88" style pistons to make up for the different stroke so you don't shove the piston into the head,but yes the cylinders are the same. HTH  Coff 06

[Admiral Akbar]

If new cylinders are bought, the mechanic takes it apart and immediately begins putting it back together.

You'd think that after pulling 10-20 sets from guys that don't want to get 20 bucz on sleazybay, they'd get em all bored and run an exchange.. Only thing is the quality of the bore and custom fitting the pistons to the cylinders..

Excuse me now as I see Red coming at me with a club... Gotta go..  Max

[wfolarry]

I used to do that for them Max but they were told to use new stuff or void the warranty IIRC. Don't quote me on this I'd have to double check it.

[BikerJim44]

Max, I know what you mean about the having the stockers bored. I have probably ten sets of stock 88" jugs hanging around. I thought about that too, having them bored but then you run into the slug problem. I like to send the slugs with the jugs so they are bore matched. At least we hope for the proper fit that way.
Also with what I gained from the answers given, my 88/95 torque plates will work on the 96" jugs? Thanks guys. Spidey.

[rigidthumper]

Yep, Jim, your torque plates will work fine. The local machinists want almost as much for boring as a new set, and there's something about "new" that appeals to lots of  folks.
Robin

[Admiral Akbar]

Max, I know what you mean about the having the stockers bored. I have probably ten sets of stock 88" jugs hanging around. I thought about that too, having them bored but then you run into the slug problem. I like to send the slugs with the jugs so they are bore matched. At least we hope for the proper fit that way.
Also with what I gained from the answers given, my 88/95 torque plates will work on the 96" jugs? Thanks guys. Spidey.

Heck you got the plates.. Get a hone and finish them you self..

Max