1954 KHRM

Hi everyone,

I've just bought a set of pretty-well bare '54 KHRM cases and have been trying to find out about them with little success.

Can anyone out there point me in the direction of some good info sources, parts, etc? How many of these were produced?

I've done a search through the archives here and see that others have or used to have examples of these bikes; if any of you could email me with info it would be greatly appreciated.

My first flathead!

All the best,

Simon

'54 was the first year for the KHRM. It was a Trials machine. Basically a KH lower end, not ball bearing as the KR's were.
Parts for this machine are few and far between as only a handfull were built David Jackson in San Antonio, TX has built two of them. He made a few contacts for repo KHRM parts. Contact him at Jackson Jewelry and eyeglass repair in San Antonio.

Thanks for the leads Chris. There are some good pics in the archives of this site, as well as at http://www.harleykrxlrtt.com/.

I'll do a bit more research and contact Dave in the near future.

Cheers,

Simon

Okay, cases now picked up and examined. Mis-matched, unfortunately, but that's okay as the price was right. What I have are:

LHS:

VIN: 54KHRM2XXX
Casting # 24534 52
5 3
Belly Number: 554-22747

RHS:

Casting # 24558 52
4 3
Belly Number: 554-1025

Numbers look good. There appears to be a weld around one of the bushes on the LHS, but well repaired. A touch of corrosion from what looks like spilled battery acid or something, but overall quite nice. RHS seems to be good.

So, now to build the thing. I have leeway with how it's built from the flywheels up, so I was wondering at what people recommend. I'm after reliability with a hint of what extra a KHRM might have had over a K. Can these things be converted to ballbearing motors, or is it better to go with something else for the street?

Should I look at standard K flywheels, rods, etc, go aftermarket, or look to what can fit from later sportster models or even tuned K variants?

I've ordered a bunch of shop and part manuals from Lonnie at Antique Cycle Supply, and am starting to look for more info as it what can run on these through the archives, but if anyone can recommend the basis of a good street engine it would be appreciated.

Many thanks,

Si

24534 52 sounds like pre-trap door?
You must use 4-9/16" (KH) or slightly larger flywheels with your tall cylinders. I suggest 4-5/8" which will allow use of replica K pistons.
IDK is this used the K/Sportster rod set and pin or the -39R set. Obviously, the K set is cheaper and stronger, and uses the cheaper Truett stroker XL wheels.
Which pump do you have/were going to use? IDK if the R pump was used here, I wouldn't - port the 1/2 pump instead.
Appears that motor came with std. KH (mild) cams, or a kit (25599-53R?) - still mild. Could use much hotter, "A" (25599-59R) my first choice. Converting cams to ball bearings a waste of money for a street engine IMHO.

You should consider using normal -54 KH or KHK cylinders - actual KHR will be very tough to find, different base casting # like 16462-54R (IIRC) so it can be ID from visual but the only diff is the 30 degree seat angle + factory relieving?

Thanks Panic. The cases are pre-trap door, with no parts other than studs and 3 out of 4 tappet guides.

I'm not sure where any of these -R parts are available - are there even any good sources for K series bikes out there?

I will probably go with readily available items from vendors such as T&O, unless I stumble across the OEM parts.

Do you mind if I ask for transmission suggestions?

Kind regards,

Simon

Belly Number: 554-22747

Oh oh! Something is very wrong with that number. H.-D. didn't build 22,747 motorcycles in 1954.

Easiest will be to treat it like a Sportster and fix what's different. T&O 4-5/8", replica XL rod set (1954-81). Any year K/Sportster pump will fit but the years closest to you may be less plumbing problems. Increase the breather timing to late XL specs or use the 1972-76 pump. With some work skirt oil can be plumbed into the original flange holes through the plugs. Replica K pistons. Any matched pair of tall cylinders - be very careful about bore size, many of these were bored to 2.875" for Scout/Atlas pistons and need sleeves so listen closely when someone says "the bore is std." - that may mean the Scout pistons are marked std. You need an actual measurement. Many are also cut for 45 exhaust valves, not easily fixable.
Transmission: the whole point is to use the 1956-69 dry clutch trap door set-up, which has been done (I had one but didn't do it). Easiest is just used parts from someone's basket case to borrow as a dummy for fit. Ratios can be selected after you know what you need, but here are some choices:
http://victorylibrary.com/tech/XL-ratio.htm

i have done lot of same work. if u use 4 5/8 wheels use low com. pistons for 45 check head to piston clearance should be .030 to .040 might have to macihne heads. there is a khrm speedo on ebay. some of the trim pieces exh. brake parts skid plate hard to find. yes treat bottom end like sportster top end like kh thanks

Deck height for K piston in KH with original 4.5625" stroke is a bit looser than what I like. It goes down by only .031" using 4-5/8" to about where I want it. May need .010" to .015" base shim maximum, no machining.
If you use 45 pistons you increase piston to head clearance by about 1/8" - very bad.

Mismatched XL/K cases are a pain in the ass!!!!,you need to machine the cases to match,personally I would give a LOT of serious thought to machining the cases for a XL trans/trapdoor.Mismatched cases present a lot of trouble with fitment,shifting,etc. If you gave more than a $100.00 for the cases,it was too much. Personally I avoid busted cases,mismatched cases.,at all costs. BREWSKI

Mismatched XL/K cases are a pain in the ass!!!!,you need to machine the cases to match,personally I would give a LOT of serious thought to machining the cases for a XL trans/trapdoor.Mismatched cases present a lot of trouble with fitment,shifting,etc. If you gave more than a $100.00 for the cases,it was too much. Personally I avoid busted cases,mismatched cases.,at all costs. BREWSKI

XLR,you need to check your private mail. BREWSKI

Brewski, thanks for the pointer on re-boring the cases. They were indeed a little more than $100, but I was interested by the KHRM designation. And as this is my first flathead, I'm happy to play around with stuff and learn as I go. This bike will probably be a road-going kr-replica, unless I can come across some of the original hardware, which is going to be a struggle.

Still, in the interest of learning about these things, starting off with bare cases is going to be a worthwhile struggle, and I welcome all of your advice and comments.

A special thanks to Jim (XLR), who entertained me today with all manner of knowledge and experience, and who has set me off down what I'm sure will be an interesting path.

Kind regards,

Si

A high school friend of mine"s dad had several HARLEY's when we were kids,Vaughn had a '68 SHOVEL when he died of emphsyma in the mid-eighties. Obviously he went to the H-D dealer quite a bit,as his son inherited a factory KH sales brochure. This announced the new trap door,bigger connecting rod bearings,different clutch,etc. Unfortunately this gem was destroyed without me getting a copy or photo.I would really advise machining the cases for a 900cc XL trans,this can be done quite easily on a BRIDGEPORT. GOOD LUCK with your project,K-MODELS are interesting bikes,still own a '56 KHK. How about posting PATRICK'S website again,I lost the address,I enjoyed talking to him,maybe he can help with some literature. BREWSKI