Trike wheel balancing

[Bacardi]

Upon take-off my Aquilla's rear wheels shake and rattle everything quite severely until they eventually stop rotating. Apart from the stresses on the instrument pod, I can only assume that some other mountings at the rear must also bear the brunt.

I tried to do a static in situ balance yesterday, using the sticky weights, but because the bearings are pre-packed with grease, the procedure was not accurate and yielded only marginal improvement, as most part of it relied on guesswork.

Short of constructing a static wheel balancing setup similar to what we used to balance the superbike tackies with, has anyone got experience with removing the spinners and having them balanced by a tyre dealer? Are they normally rigged for that type of fitment on their machines and does it last, bearing in mind a supposed creep of the tyres on the rims.

Any proper solution, as usual, will be rewarded by buying you something small.

Bac

[Bacardi]

Thanx for your reply, Mr B.

The tyres are seated. I checked for ovality. The bearings are sound (you visited once when I replaced same).

I do not experience any wobbly effects when on terra firma (even on the ODI surface), it is only when these buggers start running free after take-off that the recurrent resonant shuddering starts, looks really bad on the video cam catching the pod, which to me points at a balancing problem. As mentioned, a crude tweaking with some weights helped some, but the blighters need some serious static or dynamic balancing. Who can do this?

Greets

Bac

[Harlequin]

Morning.
I have the same problem; I stop the front wheel after takeoff but get the shudder from the rear.
Guilty of just accepting the problem without hunting for a solution.
Will quiz some of the chaps for a possible balancing answer. Please keep us posted.
Fly safely.
Graham

[Dre'man]

Check how well everything is held in place, if wheel is off the ground is there any play? balancing would affect it on the ground as well. it sounds like there is a little lateral play.

[Morph]

yes this is an ongoing problem. look carefully at the tyres, there is a red dot (usually) somwhere on the sidewall. This dot must line up with the inflation valve.

Otherwise I would try the bike tyre places that put tyres onto quads. Perhaps they have a balancing machine.

Here is a method of balancing without a machine

1. Lift the trike and try to get the wheel as close to perfectly vertical as possible, use a spirit level.
2. Spin the wheel and check that it rotates rotates freely. If you notice that your wheel has a jerky motion to it or it seems to come to an abrupt stop check and/or replace your wheel bearings. Also while you are watching your wheels spin you can check the wheels, rotors and tyres for any out of round (up and down) or warp (side to side) conditions. Should you find either, fix that problem before going any further.

3. Give the wheel a good spin so that it spins for a little while before stopping. You want the first couple spins to be fast so you loosen up the grease in the bearings. Mark the high spot with chalk. Spin again and mark. Do this at least three times.

4. Now you should have three or more marks most likely in the same area of the tire. The mean of all the marks is the light spot. Tape a wheel weight in place temporarily, with scotch or duct tape. How much weight to use depends on how far apart the marks are. If they are far apart use less weight. If they are closer use more.

5. Spin the wheel again, mark the high spot. Is it the same as the first set of marks? Tape on a larger weight in place of the smaller. Does the wheel stop at a place 180 degrees around from the first set of marks? Remove the first weight and replace with a smaller weight. Continue this until your marks are random when you spin the wheel six or seven times.

6. Your next step is to semi-permanently attach the weights to the wheels. Using the tape weights makes this pretty easy. Remove the backing from the glue surface of the tape weight and press onto the wheel in the exact location where it was taped. Of course this area must be cleansed of all grease, oil and dirt for the tape to stick well. Next apply a bead of silicon sealer around the edge of the tape weight and, with a moistened fingertip, smooth the sealer around and over the weight. This will help keep dirt and oils from between the adhesive tape and lead weight or the wheel surface.


Hope this helps.

[Bacardi]

Hi Morph

Thanks for the advice. You have pointed me in the right direction. My attempt at doing the above static balancing did not work well as the bearings were cold. I will do a couple of short circuits and long bumps next time and repeat the attempt when they are hot and loose. (or maybe just run it up and down the runway a few times)

Regards

[Slabfish]

Have you ever used the earosol puncture-fix on your a/c before,if so,then that can allso cause the problem,aspecialy if used more than once.

[Bacardi]

No tyre-weld stuff, but I can see that it will have an effect, thanks.

[allcylinders]

Not sure how well it would work for a trike, but we used to use a self balancing liquid that lines the inside of an off road motorbike tyre, as you ride the stuff spreads itself around the inside of the tyre and does some kind of self balancing trick. It was actually used to prevent punctures whilst patrolling the boarder. Only issue might be that I think this stuff settles if left for long periods which could happen with trike. Unfortunately cannot give you the name of the stuff, we used to get it in unmarked 20 litre containers, a thick gooey green or blue substance.

As I said not sure of the suitability, but might send a brain spark in another direction.

[Perry]

Folks,

Just modify and install set of rear brakes - we use the no flat tyre goop to save flat tyres on landing and also dab the brakes shortly after take-off to remove unnecessary vibration.

The installation of three way braking is also great for slowing down when loaded and wishing to hold short.

Best way of installing is providing a second cable to the pedal that levers two separate cables to each wheel. I am sure you can mod your wheels to either take a small drum or disc brake similar to that used on mountain bikes.

Regards

Perry

[grostek]

Hi Perry,

Any details/pics as well as info about weight and suppliers please?

Kind regards

Gunter Rostek

[MADDOG]

I did the static balance thing. It is rather difficult to pick the balance spot due to the bearing drag, but in the end it did improve things a lot.

Cheers