Bonneville America Forums Forums Technical Forums General Tech Look Ma no hands - Crikey!!!

Hey all.

Took my hands briefly off the bars of my new 09 America (to do up a loose glove) and within 3 seconds the front had developed a speed wobble that was getting rapidly worse - it would be dangerously violent in 4-5seconds if I had let it go.

I suspect the front wheel is out of balance and it is yet to get it's first service. There is no discernable vibration or wobble while the bars are held normally.

Never had this issue with my previous bike - you could coast (decellerate) with no hands for as long as you wanted. Not that I want to ride with no hands - I just want to clarify any issue that I should get fixed under warranty.

So what are your experiences of no hands?

Many of us have found that to be the front tire.

Cupped tires are a common cause, but if you are approaching your very first service, I doubt that's an issue. Low air pressure can do that as well as too much weight on the rear/too soft of a shock setting. Beyond that, let the dealer sort it out while it's under warranty.

Have the steering head bearing torque checked.

Deon - The tyres are new (600kms). Tyre pressure front 30psi. No additional weight on rear. I weigh 85kgs (180lbs). Rear preload set to 2 (standard factory setting). I agree the dealer should sort it out but I want to go there informed so as not to be fobbed off with "they all do that" or "that's not covered by warranty".

Rob - that's a good point - I will check this if I can and certainly suggest it to the dealer. does anyone think it could simply be the front wheel out of balance?

I have an 07. I had a shimmy from the start which seemed to progressivly get worst. Only on decel and from around 90 down to 50 kph. At around 1,000 kms, was pretty bad. Had fron tyre balanced and it was spot on.

Took it to dealer, and they replaced front tyre FOC. Apparently there is a problem with some of the Metzler tyres in that they get an out of round condition. It balances OK on both static and dynamic balancing machines but you get the shimmy under load.

Repalced with same brand and just hit 10,000kms without any issues.

So, if everything is jake with the tires/wheels/suspension, and a rider took his both hands off the bars, the bike should track straight, assuming level road etc.? Not advocating, just curious. If so, it should steer somewhat simply by leaning into a turn slightly, no? It worked this way with my old Honda CB350, but the America has that steeper fork angle.....

Mine has that same tendancy. Almost anytime I release the bars, the front end wants to oscillate. I don't think it's the tire.

I installed tapered head bearings to fix this issue on my bike. I am thoroughly satisfied with the results!

I had the problem too, but I lowered the pressure to about 28 psi, and it's completely gone.

I let go of my bars for as long as the bike will keep rolling with no shimmy. I can even lean and steer around corners with no hands and it is straight and smooth.

I spoke to Des Roberts - a highly respected mechanic here in Brisbane and he reckons it's the steering head bearings - either simply needs tightening, greasing or likely replacing.

"Replacing!" I exclaimed "it's a new bike". Yeah he said it is quite common with new Triumph Bonnies & Americas to have the bottom bearing rusted up. Apparently they don't put very much grease in the lower bearing and the steering lock gives direct access to water to run down inside the bearing cavity. Hosing around the steering lock is not a good idea.

He said it is unlikely to be the tire or wheel balance.

That's funny since so many have found it to be the tire. Wendy's bike had the wobble and I put a new tire on it and it went away. The old tire looked fine but apparently it wasn't.

Well, let us know what you come up with. Like I said in my previous post, tyre change fixed my problem. It went from a very agressive shimmy to smooth as silk. I doubt the dealer would have given me a new tyre under warranty if he didn't have to...

My wobble increases when I have the luggage rack on. Not bad though.

I had the same problem with my bike , wicked wobble when you did the " look ma no hands! " It was a new bike , low miles , Metzler lasertec tire. Took it to the dealer, who couldn't find the problem. I changed the front tire to a Metzler ME880 and totally cured the prob. Now I can take my hands off the grips at 50 mph and coast all the way down to 15 mph and it is ROCK SOLID.

I too have a serious shimmy, even if I take one hand off the bars. Due for a service soon so I'll get them to check out the head bearing. Can't spring for a new tyre yet !

It'll be a couple of weeks before I put the bike in for its 1st service - I'll find out then and let yers know.

Let old Des know too. I think he's way off the mark on this one.

Talked to my dealer's service mgr. on this issue, (he is also a big Honda dealer) and he stated that they see this wobble problem a lot with many makes and models, from Gold Wings to dirt bikes. On many of the gold Wings the factory was attaching a large heavy weight to the triclamps to dampen the vibs(my GL1100 had that). Anyway, he said the Honda owners were pretty fired up about spending that much cabbage and having a wobble, and that owners had spent thousands seeking a cure, often not found. He also said that the wobble, between 45-40 mph on decel, ususally disappeared above and below that speed, and that it usually got worse as the tire wore. Told me to bring mine in and they would check it, but I dunno. It'll either get better or it'll get worse, so for now I'll just ride.
PS: My new Progresive fork springs - outfreakinstanding. Dive gone byebye.

Wendy's had the wobble and tire looked perfect, tons of tread lest no visible cupping or anything. Changed the tire and no more wobble at all, not even a little.

This thread has reminded me that I need to ask the group about tire wear. The stock Metzler on the front of mine is just about worn out. Oddly, it seems that the tread on one side is thinner than on the other. The bike seems to track OK though. Anyway, is it normal to replace the front tire at about 9K miles?

My stock front Metz. is still on my bike at about 21,000 miles and gonna go at least this season yet. Tread wear is even.

Which Metz is that? Mine will probably be showing the belt in another 2K.

The one that came on the 04, Lazertech.

Well, they've apparently changed something in the forumula. My back tire is doing better, but I hate the way it handles in the corners. Even mild leaning feels like I'm on Jello. A buddy with a Sportster put on Metzlers and had the same problem. I'm thinking about switching to Dunlop, but not sure which would be the best tread design for general riding. Don't care much for the new style tires (like the rear Metz on mine) with large patches of solid rubber. Guess I need to research this pretty quickly.

I had a front end shake and trued the rear axel up. front end shake went away. The knotches on the axel nut, adjusters, are not right. This is cheep, quick, and easy. Check the easy stuff first, especialy when it's free!

I have a feeling that the slightly exaggerated angle of our forks sets off a strange harmonic, that becomes readily apparent when any imperfections are present in the tread.

A note from days of yore: I used to haul tankers and flatbeds. When loaded just so, the 40 ton GVW flatbeds and bulk tankers would jump up & down a half or quarter inch at around 2 or 3 cycles per second on a perfectly flat road at certain speeds, usually around 40 to 45 MPH. Weird harmonics. Suspension bridges do this too. It's pretty 'exciting' to stop in traffic on the George Washington Bridge, and the entire 3,500' span is jumping up & down an inch or so.

UPDATE
Well the dealer checked it out on the first service. He said that after a test ride the wobble was so slight that touching the bars with a finger was all it needed to go away. They checked the steering head bearing and said it was torqued perfectly. So he reckoned it wasn't worth worrying about. I said, "Worry about it." He said he would ask Triumph about a warranty claim.

Apparently Triumph said the tyre may be out of round, and that you shouldn't be riding with no hands.

I replied, "That's bl**dy flippant - this is supposed to be a quality product - balanced and aligned - I expect more than a smart comment."

I said I would check for out of round. I have done this and the tyre appears to be fine.

So I'm not sure what to do next. If it is the tyre then the problem will eventually be resolved when I put a new tyre on. However - if it is not the tyre the bike would probably be out of warranty by then - and I'm stuffed.

It is not a major issue - there is no vibration when holding the bars - but it irks me to think that my dream bike is a less precisely engineered than my ex-Yamaha that was only half the price and that Triumph could care less.