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k model cam gear size

Post Sat Jan 22, 2011 8:39 am

Posts: 11
im restoring a 52 k model basket case.the cams that come with it arnt marked with a k or kh etc but 1,2,3,4...the gear thickness on all of them is .4325...i have a couple spare cams marked 3k an 2kh etc that have thickness of the gear at .582,overall length is the same for compared to the number 3 and the 3k its 3.025 long. the #2 and the 2kh is 3.625 long,the spare 4kh and the #4 cam is 3.325 long etc...the lift of the lobe is .385 measuring down to the shaft next to the gear side on my 1234 set and on the 3 k its the same as well,the 2kh cam is less at .360,the 4kh is .360 as well,gear dia. is the same on all as the pitch is well as the gear height..the only diff i see is the lobe width is bigger and less of a angle on the 2 kh,4kh and 1234 cams and the 3 k has a narrower lobe and less durationand alot more of a angle .question is did harley mark early k model cams with out the k letter and just have numbers?or i know sportsters had numbers and letters but did they just have numbers?
the gear thickness is the only differance i could find when i measered all the cams for comparision.i measured 10 different lengths and diameters on all.
also i need a few parts to complete the bike and any leads on parts would be apreachited...
battery carrier rods,terminal plate,kick starter shaft and innerds...can i use a early sporty kicker assembly?,manifold ,1 tappet and 2 exhaust valves plus seals and gear spacers...aside from that the bike is all mostly 52 k and i would like to keep it as orig as possible,it was the bronze color under a few layers of paint so im repainting it the same color.
biggest prob i see is 3 old fixs and welds around the main and counter shaft,i was looking for a right side case with less or no damage in that area but still no luck,has anyone had luck with having that area cut out and a new insert welded in and if so who does that work?
any help or tips would be greatly apreachited...

Post Sat Jan 22, 2011 3:22 pm

Posts: 575
Location: devon,england
nice to meet you. i have cam s that are maked 1234 and are khk grinds so ...who knows. post some pictures. :D
Dude, check out that jibhead, he's crazy. Hasn't been sober for 40 years

Post Sat Jan 22, 2011 6:45 pm

Posts: 11
good to meet you too post some pics but im on dial up and that takes so long my computer would disconnect befor download could complete.they fit and cover will seat properlly,line up with tappets etc so ill still use them ...ill see what i can do about pics of cams and maybe the bike in progress.curently in dining room...

Post Sun Jan 23, 2011 3:53 am

Posts: 591
Location: Crewe, Great Britain

Hi, ezerider

Main difference between K and KH cams is the length of the shaft on the cam side of the cam gears. K are much longer there cause the cases were cast as the W style, with casting stiking inside the crank cavity. That's also why you have a pressed in crank pin and no nuts in the K.

The KH came with a tapered crankpin and nuts. To accommodate that, the protuding casting was machined off and the cam shaft was shortened to suit.

- K cam = long shafts and stamped K, wide gears, very mild cam grind and lift
- KH cam = short shafts and stamped KH, wide gears, just about OK cam grind, same lift as K
- Cams stamped 1 to 4 are indeed KK and KHK cams, these high lift/long duration cams are derived from early KR that had crankpin taper and nuts so all have short shafts and thin gears for less drag. If you want to use them on your K, you'll have to machine the heads for more clearance, with valves fully opened, you need about .120 free space above the intakes and about .080 above the exhausts. It's also wise with KK/KHK cams to shim the valve springs, about .040 from coil bind to give you maximum spring pressure as these cams have much higher acceleration on opening and desceleration on closing, to avoid valve bounce.

can i use a early sporty kicker assembly?,

If you have the proper thin K primary cover, without oil level plug, this restricts you to the 5 plates thin clutch drum. KH clutch drum is wider, for 7 plates hence its wider primary cover.

Since K and KH kicker have a different ratio than the Sportster, you can only use the Sportster complete kicker/clutch drum on a KH.

As for swapping cases, don't... More hassle than it's worth... My KHK was rewelded when I bought it 27 years ago, it's been rewelded once since and it's holding OK despite the WOT style of my riding... Just have it checked and reweld if necessary...


Post Sun Jan 23, 2011 11:14 am

Posts: 11
thanks patrick,i checked the length and it is .125 longer at that end,i have a spare set of heads off a 54 i beleave that have been recessed for more valve lift so ill use them .ill be sure to check valve lift during final assembly.,i will shim the valve springs as well,they do look agressive compared to the stock k cams i have,(just dont have a complete set) so ill use the khk set.
i do have the proper 52 k cover with the 5 plate set so guess that narrows my search to a 52,53 kicker shaft and drum set only.
thanks for the tips...

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