Lean In?

They've had that for years.
They work better with a bit of lean out.

Lonnie
Northwest Sidecars

All rigs handle different. How is your tire wear? How does it feel to you? Is it pulling one way or the other? In part the different come from how and where you ride.

I have a theory about the “lean in” recommendation in the Harley sidecar service manual. Thank the lawyers. If you set it up with lean in, it will handle like crap and pull to the right a bunch. But, it will be much harder to lift the sidecar wheel in a right turn.

If you have 1 degree negative lean unloaded, when the bike rider climbs on the bike will be upright or lean away from the car depending on the weight of the rider. Remember with a Harley Factory rig the bike sags and the sidecar does not as weight is added to the rig. The passenger weight in the sidecar also contributes to bike sag rather then sidecar sag. This is due to the antiquated design of the unsprung suspension the Harley Factory sidecar uses. Just follow the second part of the manual where it says to adjust the lean so the rig will track straight when used under your personal rider/passenger/speed/road conditions. Many will also suggest cutting back on the toe-in to a little less then 1/2" for most conditions.

I think Tod has it spot on.

The trick to adjusting "Lean" for best performance on a rigid wheel rig like the HD's would be to do it loaded after doing the static setup.
The 1% Lean In with no load would likely work out just fine most of the time once the load was applied and checked by a third person.

I agre with Todd (tkpinsc).
Harley sidecars have no suspension on the sidecar other than what the tire itself may provide. Antiquated? Well IMHO not really. It is an old design but works pretty darn good. Heck, racing sidecars from Formula I on down have no sidecar suspension either and they go pretty good. Sure this may be mandated for safety and other reasons but the fact remains that they do work well.
Anyhow, with a rigid sidecar 'suspension' lean in or lean out will stil have the same final results as with a more conventional sprung sidecars. That means if we just think of lean adjsutmets as being 'lean bike left to go left and lean bike right to go right ' we can dial in a rig to work the best for us on a personal level.
Toe in to me shoudl be minimal. We typically set up a rig with between 1/2 and 3/4" of toe in. From there checking tire wear patterns can give clues on whether we are at the best place or if we should adjust it some more. Too much toe in will eat tires.
When lean out is adjusted toe in shoudl be rechecked.

Any design older then me is antiquated. I made no judgement or comment about how well it functions, just it's age. ;>)

Originally written by tkpinsc on 3/25/2008 8:23 PM

Any design older then me is antiquated. I made no judgement or comment about how well it functions, just it's age. ;>)

Well then....hmmm...oh never mind.

So TK, you were born before 1914? ;).....

....Anyway, back in Pittsburgh Pa., I found one of the old timers who used to do the set-ups for the police bikes, and he set my rig up. Originally he set the toe at 1/2" and 0 lean on the bike....and it pulled to the right quite a bit on the freeway....so he adjusted the toe 1/2 turn back and put a slight left lean on the bike..(he didn't use a protractor on the brake disc like Harley says, he just stood 15 ft. behind the rig and eyed her up). My tires wear evenly and I can eat a sandwich and drink a pop at 70 mph......almost:)...

I said its antiquated cause its OLDER then me.

on mine ive done a lot of checking - it has to lean in unloaded to be zero loaded - when the passenger gets in the car the bike leans out.

so, ya the book is about right - asssssssuming you have stock shocks. if you have lowered or stiffer shocks start out with zero unloaded

to

...And I say you must have been born BEFORE 1914....which makes you OLDER than the very capable and proven design in use today.

Timo,

I have my stock shocks aired up pretty high, near max psi. I usually have the tour pack and saddle bags loaded down, and at 180 lbs. I might not be zeroing the bike out.

As others have said. the reason HD uses 1 degree lean-in is so that the bike will be approximately vertical with the rider in position. They spell this out in the sidecar manuals. (P/N 99485-XX) They also specify 3/4" to 1" toe-in. I use the 1 degree lean-in and 3/4" toe-in and the bike steers quite neutral.

A fine point that is covered in the manuals and which is frequently ignored is that the frame must be parallel to the ground. Since the wheel is at 90 degrees to the rear frame tube, that will guarantee that the wheel is absolutely vertical. This is important to prevent unwanted pull, even if lean and toe are correct.

As far as the HD not having separate suspension on the sidecar wheel, I am glad. That prevents it from getting mushy. Also, since the wheel is out a good distance,(54"+/-) the HD sidecar has a nice long moment arm to prevent undue movement on the bike, even if the wheel does move over bumps.

The HD design is tried and true. I like 'em! That's my story and, as usual, I'm stickin' to it.

P.S. Please place flames, ridicule, contradictions, negative discussions about my ancestry and incorrect, misguided, technical rebuttal below this line:
(LOL)
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