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k model ,flat tappet kit

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Post Wed Jul 13, 2011 5:40 pm
jib

Posts: 575
Location: devon,england
hi guys, on ebay ,with one day to run is a oem,harley complete flat tappet kit for a k model, springs,valves,cams,tappet followers,guides and spring stools. the whol kaboodle.
never seen or heard anything about these, anyone got any knowledge?

http://cgi.ebay.co.uk/HARLEY-CAM-GEARS- ... 1e64fb92a6

regrds jib
Dude, check out that jibhead, he's crazy. Hasn't been sober for 40 years

Post Thu Jul 14, 2011 8:39 pm

Posts: 159
You got me there! No idea they existed. Did KR's use this system?

Post Sun Jul 17, 2011 9:46 pm

Posts: 391
KRMs used them. And they do not interchange with WR components. The flat tappets are flat bottomed not angled as WRs are due to the holes in the case having the angle built in. Old timers claim they were the worst cams to be used in KRMs and most changed them to regular KR or KK/KHK types.
Robbie

Post Mon Jul 18, 2011 2:31 am
jib

Posts: 575
Location: devon,england
hi robbie, wouldnt the wr flat tappets be flat too, only the cams being angle ground ,as the tappet blocks had the correct angle bored in them to give the alignment .?
so the flat tappets in both krm and wr being the same only the tappet blocks being different ? regards jib
Dude, check out that jibhead, he's crazy. Hasn't been sober for 40 years

Post Mon Jul 18, 2011 9:30 am

Posts: 131
Location: BRANFORD, CT

Hi Guys,

I believe all the K models had roller tappets and did not produce a KR untill 54.
This was probably a kit to upgrade to a racer similar to the WR kits made for the WL
Cams have typical WR sharp corners and appear to be ground straight without a angle and probably are WR.
Tappets are straight (flat) and should have an angle.
Tappet guides are straight and are threaded like the KR, I can't tell the width, but the straight tappet is wider than the roller so you can't use a regular K guide without making it wider.
On the K models the hole in the case for the guide is angled where as in the WR the holes for the guides were straight and the guides had the angles.

Jib,
On the WR the cams are straight and the tappets are straight (flat) but ground at an angle (the term flat is misleading).
The tappet angles are different between the WR and the K, people do interchange them, but you have wear problems. Ask Dr. Dick.
WR lobes will work in this application as they are (you have to change the shafts) but the WR tappets would have to be reground straight with the correct angles to match the holes in the cases. Intake and exhausts are both different.
Actually the WR profiles are not really that hot compared to the KR profiles. It’s the limitation of the straight (flat) tappet.
And NO! do not even attempt to use roller tappets with the WR profile. It gives you completely wrong valve timming.

Does this confuse any one any more?

Bruce
http://www.enfieldracing.com
Bruce Argetsinger
AHRMA Dirt Track # 67J
www.enfieldracing.com

Post Mon Jul 18, 2011 10:35 am

Posts: 767
Location: CA USA
For anyone still confused about the WR flat tappets please got to the Beauty of Speed website. The Workshop area has copies of the original Harley Davidson blueprints for the WR flat tappets showing the precise angles for each along with the hardening specs.

Post Mon Jul 18, 2011 6:24 pm

Posts: 391
Jib,
The angled tappet guides on WRs only allowed a certain amount of angle due to the constraints of the straight bored case (They were bored straight like every other 45) in relation to the cylinder location.
K models had angled and aligned bores making the alignment easier due to being designed for angled valves.
So to make up the angle differences the WR tappets are angled for each individual valve and are marked as such (eg; RE, RI), On the K flat tappets the angle is the same on all of them and thee are just front and rear versions. My '54 competition list shows the pieces, but not as a kit like the WR kit but only individually. I don't know if earlier lists show the kit, however the WR kit is still listed in '54 so I would think that if they offered a kit it would still be there.
Robbie

Post Mon Jul 18, 2011 8:01 pm

Posts: 159
My head hurts! All these years not having handled a WR, i presumed the holes for the cases were angled like K's and KH's!

Post Mon Jul 18, 2011 9:22 pm

Posts: 391
My head hurts! All these years not having handled a WR, i presumed the holes for the cases were angled like K's and KH's!

Nope, straight bore parallel to the cylinders. So a WR valve train actually makes a bend in the middle! One angle on the cam, another on the tappet. Fun isn't it! :mrgreen:
Robbie


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