MKII crank

Hay guys,new to the board but been viewing for a long time. Loads of good info hear for sure and definitly considerate group of people, Thanks.. First question I have is about the crank in my 1980 KZ1000. I totally restored this bike last year minus doing the engine properly. I am planning on pulling the engine and glass blasting the cases and chemical cleaning them (to remove any glass particals). I figured while the engine was apart it would be a good time to update or strengthine the lower end. The mods are moderate at best,Web 118 cams, 29mm smoothbores, pods and 4 into 1 V&H header. I am thinking of having what I call (cleanup) porting done. Would it be wise to have the crank checked for straightness and have it welded? How about main studs? I have a habbit of upgrading things as the bike starts to (feel) slow if ya know what I mean... Thanks Ben.

as long as it already has a big pin crank i would go ahead and use it just have it checked for straightness and the pins welded.if you are just going for a mild rebuild case studs would probably be unnecasary(spell check! )mkII motors have a overkill bottemend compared to the 73-78 versions which really domt need a whole lot themselves.goodluck,happy wrenching;)

I was hopping thats all that would be needed. I'm in Mi, is there anybody close by who welds and straightens these cranks. Distance is not as big a deal to me as quality though. Thanks Ben

Many of the leading tool supply companies have precision ground steel rod in three foot lengths in metric sizes. Most call it drill rod.

You can get a 17 mm diameter piece for about $23.00.

This is what you use to check it the crank is in index. If it will fit thru all four rods, the crank is OK. If the crank is twisted out of index, the rod will ususllu go thru three rods, but not the last one.

Jay

Post edited by: APE Jay, at: 2006/12/25 01:02

Even cheaper at MSC $18.95

wireman wrote:

as long as it already has a big pin crank i would go ahead and use it just have it checked for straightness and the pins welded.if you are just going for a mild rebuild case studs would probably be unnecasary(spell check! )mkII motors have a overkill bottemend compared to the 73-78 versions which really domt need a whole lot themselves.goodluck,happy wrenching;)

not to hijack the thread but wireman you should look into using mozilla firefox as a web browser.. it has a built in spell checker that is just dandy!

Thanks, there are a couple places near me that do sell precision ground rod that i know of. Weather thay have that size will hust to wait and see. Ben

While you have the engine apart, I would install the APE case studs and cylinder studs and add the crank support plate. Cheap insurance for the cost imho. Same thing for truing and welding the crank, MKll's have strong cases/cranks but these mods are worth the peace of mind to me.

Your right and I was planning on doing all of those after reading what everyone on hear has had to say. I'm not one to cut corners ether. I'd rather over build than under build any day. Ben

Jack,

APE does not list a crank support plate for the MKII, are you using the one they list for the 73-78 1000?


Jack wrote:

While you have the engine apart, I would install the APE case studs and cylinder studs and add the crank support plate. Cheap insurance for the cost imho. Same thing for truing and welding the crank, MKll's have strong cases/cranks but these mods are worth the peace of mind to me.

It is the same.

Jay

Good to know! I have a B4 and will be doing a little engine work one of these days.