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KR crank options?

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panic

Post Sat Jan 12, 2008 11:32 am

Re: KR crank options?

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Last edited by panic on Sat Jan 12, 2008 6:24 pm, edited 1 time in total.
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thefrenchowl

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Post Sat Jan 12, 2008 11:59 am

Re: KR crank options?

Hi panic,

As I said, 52/53 KR had the WR type crankshafts in it, so your dimms might relate to these earlier thin on the ground KR motors.

What I know for sure is that my XLRTT, restamped motor, probably made in 1960, is all metric, stated metric sizes which were the same as KR and it was bought in Wisconsin!!!

I also have the factory drg for ball bearing gear box sprocket rather than loose rollers, dated 1958, it says to use the drive side crank bearing, 9030R, dimms in inch as follows which translate in 25 x 52 x 15!!! : shaft .9839, OD bore 2"0476... The 9 cam ball bearings (2 of them in the magneto iddler gear) are also metric, 9 x 24 x 7, the only one bearing that might still be inch is the Torrington needle roller that can replace the #2 cam big bush in the timing cover.

My spacer set up uses all the std street bits: oil seal and carrier, sprocket, only the shafts are ground down to 25mm.

Patrick
Last edited by thefrenchowl on Sat Jan 12, 2008 12:19 pm, edited 1 time in total.
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thefrenchowl

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Post Sat Jan 12, 2008 12:18 pm

Re: KR crank options?

Panic, I still had a niggling doubt so I've just looked at the KR parts book...

Sprocket shaft is XLR/KR/WR, a 41R item at least till 1959 and goes with ball bearing 9030R which is the metric one. The one to use in the gear box as well.

Timing shaft XLR/KR is a 52R, so different from WR, goes with bearing 9031R, so I'm pretty sure that's the smaller OD metric one as well...

Patrick
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slindo

Posts: 66

Joined: Tue Jan 08, 2008 7:25 pm

Post Sat Jan 12, 2008 1:52 pm

Re: KR crank options?

I still find it hard to believe that HD, back in the 50's, or 40's for that matter, would have used godless satanic unamerican metric bearings, though I claim no particular expertise on the subject. How are you inferring from those part #s that they are metric.

BTW, has anyone ever seen or compiled a list of HD bearings and their industry-standard equivilents? It would be very useful if there was such a thing.

Oh, Panic, are those bearings you list WR, K, Xl, KR or ??

thefrenchowl wrote:Panic, I still had a niggling doubt so I've just looked at the KR parts book...

Sprocket shaft is XLR/KR/WR, a 41R item at least till 1959 and goes with ball bearing 9030R which is the metric one. The one to use in the gear box as well.

Timing shaft XLR/KR is a 52R, so different from WR, goes with bearing 9031R, so I'm pretty sure that's the smaller OD metric one as well...

Patrick
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thefrenchowl

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Post Sat Jan 12, 2008 4:15 pm

Re: KR crank options?

The reason for metrification for these bearing is probably more to do with ISO standards and because they were, even in these days, quite widely available, probably cheaper?

By the way, I still have in a draw my XLRTT original ball bearings, I can vouch they are metric, as stated by the old factory drgs I've got. These dimms lasted until the late 70's when the high reving alloy XR engine went for barrel keg rollers, again metric sizes...

This KR/XLR manual page on my site, dimms clearly show bearing 9030R is metric:

http://www.harleykrxlrtt.com/images/0%20tech%20kr%20gear%20bearingsm.bmp

ID .9839" x 25.4 = 25mm, OD 2"0476 x 25.4 = 52mm

Patrick
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panic

Post Sat Jan 12, 2008 6:20 pm

Re: KR crank options?

Sorry, can't find my source.
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slindo

Posts: 66

Joined: Tue Jan 08, 2008 7:25 pm

Post Sun Jan 13, 2008 11:36 am

Re: KR crank options?

Pretty hard to argue with that. Thanks!

thefrenchowl wrote:This KR/XLR manual page on my site, dimms clearly show bearing 9030R is metric:

http://www.harleykrxlrtt.com/images/0%20tech%20kr%20gear%20bearingsm.bmp

ID .9839" x 25.4 = 25mm, OD 2"0476 x 25.4 = 52mm

Patrick
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slindo

Posts: 66

Joined: Tue Jan 08, 2008 7:25 pm

Post Tue Jan 15, 2008 11:45 am

Re: KR crank options?

Just heard back from S&S:

> We still make new wheel halves for the WR/KR
> engines. The part number is
> 32-3013. You will need to order a special crankpin
> for these wheels that
> accepts the early sportster or stock 45" KR rods.
> The part number is
> 34-2513. We have a WR/KR sprocket and WR pinion
> shaft in our new
> catalog. The part numbers are 33-2351 and 33-2355,
> respectfully. We do
> not rework stock sportster wheels to accept the
> early model shafts.

MSR for flywheel pair is $$$, the crankpin $$$, and the mainshaft $$$. email or PM for prices
I suspect they are confused about the crankpin.
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37ULH

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Post Tue Jan 15, 2008 10:27 pm

Re: KR crank options?

The nuts that you get with it are more unique than the crank pin. ( and necessary)
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panic

Post Wed Jan 16, 2008 9:23 am

Re: KR crank options?

Confused is a bit more flattering term than I would use: "no clue whatever".

And if you buy these (other than the enormous $$$ damage and a rod set) when will you know if they fit your cases (since they're WR, not KR)?
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slindo

Posts: 66

Joined: Tue Jan 08, 2008 7:25 pm

Post Wed Jan 16, 2008 8:25 pm

Re: KR crank options?

I find a lot of the time that there is one person at a company who "knows things" and the people who answer the phone and email have to pry the info out of them, and it often gets garbled. So it can take few tries, either to get the correct info, or until they get sick of dealing with you and put you directly in touch with the person who really knows. I suspect here someone just mistook K for KR.

What is your concern about fit? Wasn't it established earlier in this thread that KR and WR flywheels are very similar, apart from the crank pin? This would seem to make the S&S WR/KR crank, which comes set up for Sportster rods, with custom T&O wheels modified to take the Sporty or KR pin. And wonder of wonder, they are priced identically too.

panic wrote:Confused is a bit more flattering term than I would use: "no clue whatever".

And if you buy these (other than the enormous $$$ damage and a rod set) when will you know if they fit your cases (since they're WR, not KR)?
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suicideshovel65

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Location: Palo Alto, CA

Post Thu Jan 17, 2008 12:22 pm

Re: KR crank options?

Can't help with eact dimensions or anything, but here are some pics of the KR and WR flywheels:

http://www.flickr.com/photos/21629196@N03/sets/
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slindo

Posts: 66

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Post Thu Jan 17, 2008 2:05 pm

Re: KR crank options?

Thanks! They are most useful, and clear up a few mysteries.

Whose parts are those anyhow? I'd really like to get some weights etc.




suicideshovel65 wrote:Can't help with eact dimensions or anything, but here are some pics of the KR and WR flywheels:

http://www.flickr.com/photos/21629196@N03/sets/
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panic

Post Thu Jan 17, 2008 5:33 pm

Re: KR crank options?

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Last edited by panic on Sat Jan 19, 2008 9:50 pm, edited 1 time in total.
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slindo

Posts: 66

Joined: Tue Jan 08, 2008 7:25 pm

Post Thu Jan 17, 2008 6:16 pm

Re: KR crank options?

Well we already know half the answer - we know that the lightened racing flywheels have less torque and require more buzzing but give faster power. This gives someone building up a WR or KR or any hot 45 half the information they need to tailor it to their needs, by using either heavy street flywheels, or light racing flywheels, or maybe something in between. But only half - without knowing the actual weights, it is very hard to get the results one wants. For example, S&S offers what they call a WR/KR flywheel. But is it more of a WR, KR or just a Sporty with different tapers? knowing the weights of the various permutations can help deduce which.
In may case, if I build up a KR, I would like to have it run like a KR, warts and all. That means having a flywheel which approximates the stock one. One of the nice things about using Sporty flywheels is that they are so cheap that one can afford to play around with them. So if I can find out the weights of some of the different flywheel permutations, I can make an informed choice of whether/how much to lighten mine.

panic wrote:"I'd really like to get some weights etc."
I really, really hate to repeat myself, but knowing what they weigh does very little for you. Posing it as a question: if the stock 45 wheels weigh 20 lbs., how different will the response be with 10 lb. wheels?
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slindo

Posts: 66

Joined: Tue Jan 08, 2008 7:25 pm

Post Fri Jan 18, 2008 10:38 am

Re: KR crank options?

Another tidbit from S&S:
"The 34-2513 crankpin is our standard 34-2503 sportster crankpin that
has
been shortened on both ends to account for the thinner section
thickness
of the WR/KR wheels. The diameter of this crankpin is 1.250", which
corresponds to an ID for the rods of around 1.625" and a width of
1.485"."
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panic

Post Fri Jan 18, 2008 10:54 am

Re: KR crank options?

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Last edited by panic on Sat Jan 19, 2008 9:50 pm, edited 1 time in total.
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thefrenchowl

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Post Fri Jan 18, 2008 12:15 pm

Re: KR crank options?

Panic:""if the stock 45 wheels weigh 20 lbs., how different will the response be with 10 lb. wheels?""

I really don't know on a H-D set of flywheels, but from what I've seen with big engines with little flywheel, it makes for unfriendly power curves.

A friend I knew in France back in the 70's bought a Munch Mammuth... that 1200cc NSU car engine normally got its flywheel effect from the huge clutch drum,but that was deleted on the bike... The response was wicked, but it was nearly undriveable unless you were a fully fledged race pilot...

Less inertia, to a point, is good, but no inertia...

The furthest I've been with me Sporties is to skim about 120 thou off the flywheels diameter, doesn't hurt the scavenging too much and brings a bit less oil drag in there. I understand it was a common drag racing mod back in the 60's

Patrick
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slindo

Posts: 66

Joined: Tue Jan 08, 2008 7:25 pm

Post Fri Jan 18, 2008 12:51 pm

Re: KR crank options?

I don't understand what you find so odd about my approach. I don't have a crank for my machine and have to find some way of cobbling one up. There are a number of parameters I have to match, to come up with as functional a replacement as possible. One of the major characteristics flywheel, that has very much to do with its performance, is its weight. Therefore, it is only logical that I try an find the weights of all the alternatives before I decide. Sure there are other important parameters, but weight is easy to measure and easy to communicate, so why not know it?

Re the S&S WR/KR wheels, I too had assumed they were just Sportster based and would be similar in weight. But the fact that they need a modified pin to fit their reduced thickness suggests that they may not be. But how then can we quantify the difference, without having examples of both to compare and examine? Weight comes to mind.

While the difference in reponse between a 20lb and a 10lb flywheel would be intellectually interesting to know, it doesn't have an relevance to what I am trying to do since I am not trying to reinvent the wheel, but am rather just trying to find out what the HD race dept in its wisdom though was best, and so I can try to come as close to that as I can, without spending too extravagantly.

I fear I am not communicating very well, as this seems very basic and non-controversial.



panic wrote:I'm going to be a bit brusque here (keeping in character).
"we know that the lightened racing flywheels have less torque and require more buzzing but give faster power"
No, we don't know this - it's not true.

"without knowing the actual weights, it is very hard to get the results one wants."
The S&S wheels are Sportster-based, and about stock weight. Both the stock 45 and Sportster are about 20 lbs.

And, again, again, what do you think "knowing the weights" do to help you plan what to do to yours? If a WR wheel set is 16 lbs., what does that mean?
As I asked before: if the stock 45 wheels weigh 20 lbs., how different will the response be with 10 lb. wheels?
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panic

Post Fri Jan 18, 2008 2:31 pm

Re: KR crank options?

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Last edited by panic on Sat Jan 19, 2008 9:51 pm, edited 1 time in total.
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