What Would Be the Standard Practice in This Situation? - 1

As has been mentioned before, a steel spacer is the best way to go. You are hampered by the thin wall that the geometry requires. You cannot make this by hand. You will need to have it made on a lathe. One way to do this is to shrink fit it (with heat) into the top clamp. Shim stock is a bad approach I think.

Jim

Reply to
jim rozen
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Hi. I agree that a steel tube is the way to go. After everyone's advice, I am not going to try the tube method by hand. If the stainless shim stock and Loc-Tite 638 do not work, then I will definitely pay someone to make me a couple of tubes/sleeves. Do you have a rough estimate of what this would cost to have made at a local machine shop? I have never had any machine shop work done, so I have no clue on how getting one to make something for me would normally go. Do they charge by the hour, plus cost of the metal, or just charge X amount for a particular job?

Thanks.

Reply to
JWho

Actually it is. That would take some effort such as partial reassembly of th' bike using th' old top triple tree and taking measurements. Then measuring th' offset difference between th' old and replacement trees and doing th' math. Th' question is, how much effort is your hide worth .

Don't know how you can come to that conclusion without knowing exactly what th' difference is. A degree or two is all it takes to make for dramatic changes.

Hold m' beer and watch this?

Snarl

Reply to
snarl

{Satire Alert for the Humor Impaired...}

If I'm following this whole mess correctly through all the Angels doing a Rockettes Dance Line on the head of a pin... ;-)

JWho is shimming where the steering bearing shaft goes through the top and bottom plates of the triple tree, right?

(The other two holes are where the fork tubes go down to the front tire, and the handlebars fasten to the top plate somehow.)

And he said something about their being nuts on the top and bottom of each plate where he needs to shim the hole, right?

So both the shims would be held 100% captive by the nuts on top and bottom, and washers on the sides toward the bearings, right?

So why the (heck) can't JWho just use a simple ring of .030 stainless shim stock (or the thickness needed) cut to the right length and Loctite'd into place? Someone please tell me, I want to know!

Common sense, My GOD! What a CONCEPT!! ;-O

Somebody call Paul Teutel Sr. and Jr. and get their opinions on this mess too, while we're at it! :-P I know Paul Sr. is in town, he just Grand Marshaled the Love Ride. If you want abuse while building a bike, he's the Go-To Guy to get it from...

{Satire Alert Off}

If that bearing shaft can't go anywhere, it should not be a problem. And if he is bushing the hole evenly he isn't changing the steering geometry at all - the hole is in the exact same place, it's just too large.

Now if the triple tree and forks combination isn't the right geometry for the bike, I can see a problem with that, but the bushing for the steering shaft would not have anything to do with that. It's just holding the shaft in the right place.

And in conclusion: Why is Common Sense so uncommon?

-->--

Reply to
Bruce L. Bergman

He sure could. He could do a lot of stuff. It would probably work. 95% of the time, for years, probably.

Heck he could stuff cardboard in there and the bike would go down the road. Yep.

Jim

Reply to
jim rozen

He could also ask one of the guys who hangs out on r.m.harley their opinion. I'd be willing to go by that.

:^)

Jim

Reply to
jim rozen

Hi. Actually, it is just the top clamp, not both the top and bottom. I know of one person who has 1,000 miles using just .025 brass shim stock to take up the gap. There are several other people who have done similar, or had a machine shop to install a bushing/sleeve/tube. NO ONE who has died has reported of a failure. :-) From my measurements, it looks like the gap between the shaft and clamp is 1.5 thousandths of an inch. I am hoping to recreate that type of fit. I think the .025 tube/shim thickness is going to be what is needed. I am trying to test fit some folded over aluminum foil to test fit and then measure that with micrometers. Unforutnately, I don't own a lathe, so I can't make up a few different sizes and just keep test fitting them until I find the right one (measurement wise). "Nope that one didn't fit, I need you to make me another one" is a whole lot of money spent on gas to a machine shop or paying someone here to do it. :-(

Thanks.

Reply to
JWho

Pay the shop to do the measuring too. They have better tools for it.

Reply to
cs_posting

On average, what does a shop charge for an hourly rate, or do they just charge per job?

Thanks.

Reply to
JWho

It varies. Basically you have to ask around. Make up a simple hand sketch (no cad program needed) of what you want. Put real dimensions on it, and put tolerances on it. The lengths are going to be +/- 0.010 or so, but the diameter will be +/- 0.001 or so, and be sure you've chosen it so it will work if arrives just at the tolerance limits.

If you show up with real numbers like that you may well get a cheaper rate. But ask around and see what shops are in the area.

Jim

Reply to
jim rozen

Big gold star, yet again, Bruce.

Gunner

"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.

Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner

Reply to
Gunner

And bring a dozen donuts when you go. Not the cheapies..but the kind from a bakery. The discount you get may surprise you.

Gunner

"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.

Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner

Reply to
Gunner

Hi. Thank you for the information. I hope I don't call too many places that require a minimum 1,000 quantity or something like that. :-)

Thanks.

Reply to
JWho

This might be a good test of the online service whose name escapes me at the moment...

Emmo (who changed the fork lengths and rear suspension a half dozen times when I was chopping my '65 Triumph back in the 70's)

Reply to
Emmo

I think it's just th' top triple tree if I'm readin' him correctly.

Those nuts do more than just secure th' top triple tree in place. More importantly, they are what sets and maintains pre-load on th' steering head bearings. Correct pre-load is kinda, sorta important.

Captive as in up and down (vertical play) correct. However as bearing pre-load changes with wear, pivitol forces can/will start hammerin' on th' shimstock. Said shimstock will wear in an oval manner, increasing as th' shimstock is further beaten as more play occurs. There's a video clip here:

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Scroll down to "Bad tank-slapping accident at Isle of Mann! (I hope this guy was ok)"

He can. Nobody said he couldn't far as I know. I sure as hell wouldn't make one with hand tools tho. But that's all after th' fact of th' point I was attempting to make. Check th' damned geometry

*before* ya even bother futzin' with it any further. What's wrong with knowing that what you're attempting to customize will be within reasonable specs? Especially on a murdersickle .

Yeah, that's what I'm talkin' about. Then again, ain't my ass if he chooses not to use any. Just hate to see a kid get hurt for no good reason... other than bein' too lazy to do a little math. Oh well.

Yeah, but it *can* move around. It can, and will pivot inside that shim with wear or improper pre-load.

Th' steering stem hole on his replacement is not in th' same place, relative to th' fork tube holes, as th' original. I can see it from th' pics. That can considerably exacerbate stresses on th' shim. I've seen this shit happen on altered motorcycles before. There's a reason his insurance co. won't touch his bike if he informs them of this modification.

That bushing will be th' weak link after bearings wear any measurable amount. Those steering neck bearings take a hell of a pounding. There's a lot of stress there. You gonna trust yer ass to it?

Can't answer that, but it surely is. I think it has somethin' to do with laziness, but can't prove it.

Snarl

Reply to
snarl

I was assuming this was for a street bike application, is it for off-road? 1,000 miles isn't anything for street bike testing. Brass huh? Sheesh.

Seems like that's yer answer right there. Have one of those machine shops who've already done this make yours.

Heh, heh.

I might've missed it, but what's th' reason for this modification again?

Snarl

Reply to
snarl

You mean this:

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Might as well do somethin' since they rarely actually ran for any length of time ; ) And yeah, I've built and ridden a custom bike er two in th' past 40 years m'self. Still do.

Snarl

Reply to
snarl

Yes, it is just the upper clamp.

The OEM stem and clamps are aluminum, so I doubt stainless steel is going to become worn in such a setting.

I think I already mentioned that I agreed with everyone and am not going to try to make a tube/sleeve/buhing by hand. If several other people already have done it, doesn't it make sense that it would be OK?

The steering stem hole IS in the same place. I think you are looking at the "representative sample" pictures. Those were to just show a general idea of the concept. I am replacing the lower clamp and stem, but using the same upper and lower bearings, as that is what the original and replacement both use.

...and the rest of me too. :-)

I am just repeating what several others have done, so it is not like I am doing something all new and untested.

As far as the bike it is on, here's a hint if you are a motorcyclist. I hope to travel 24 mph on it. Thanks for your concern on the rake, trail, clamp offset and such. If I was doing something new and revolutionary, I would be all over it, but the swap has been done for years, so it is not a concern to me.

Thanks!

Reply to
JWho

If brass was good for 1,000, and the original was aluminum, then I am thinking proper fitting stainless steel should last.

It may very well come to that.

It is to get more modern forks.

Reply to
JWho

And that's what I get for making assumptions, Doh!

Yeah, I got funny that way after m' 50th b-day for some reason .

Post all of th' measurements, including tolerances, in here and I'm sure one of us could turn that puppy for ya, m'self included.

This thread is a good example why including more info than less is a good idea when one is asking questions.

Snarl

Reply to
snarl

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