if the curve and incline of the road is good you shouldn't feel a shimmy. how was the condition of the road? is it possible that you could've hit a slight bump or imperfection in the road which could have caused the shimmy?

 

I bought my first street bike (07 Deluxe) approximately 10 weeks ago. I have been riding/learning in my local hood the entire time. I feel comfortable with the basics. I feel better about riding with traffic on busy Los Angeles streets and I earned the approval of my neighbor with 30+ years of Harley experience after he shadowed me on an hour ride. He stated that I ride like "I have owned my Deluxe for twenty years".

Anyway, I ventured into the mountains for my first "big ride" yesterday. I went on an 84 mile ride up into Azusa Canyon (Hwy 39) to Mt. Baldy and back. 2, 1/2 hours of riding with a mix of of 45 mile per hour mountain curves and 25-35 mph tight twists.

Overall, my excursion was sublime. However, I perceived a very, very slight shimmy or change in the tire's grip characteristics when rounding the higher speed (40-45 mph) turns. I was hyper sensitive and a little paranoid, but that sense or slight feel was there. On the tight full commitment 30-35 mph turns that generated higher g-forces, there was no shimmy. The grip was rock solid. It was just the higher speed long turns that produced a sense of grip change.

Is this normal?

FWIW, my tire pressures are good. I checked my spokes before the ride and they are stiff to the tug. But, spinning the rim and lightly tapping each spoke with a pencil yields a different tone from nearly every spoke. My bike has 4,400 miles on it.

Otherwise, my Deluxe rode pheonomenal! I realize it is a cruiser, but the overall handling, acceleration, and deceleration were A+.

Should the sense of grip seem totally uniform at 45 on a curve?

Thanks.

Mike

 

Tq745:

The asphalt was in good shape--dry, dust free, smooth, and uniform. It happened around every high speed sweeper and was a very slight shimmy in the front--I think. It was enough to unnerve me around the big sweepers.

Mike

 

I would check the steering head bearings for tightness as well. Are the tires on the bike the original tires? And what is "good pressure?" I find that that non stock brand tires like Metzeler or Avon have far superior gripping characteristics compared to the stock Dunlops. The round on these tires is also different allowing the bike to fall into corners much easier.

 

Hogpro:

My tires are the stock Dunlop 402F front and 402 rear. Honestly, both tires look new to me (I bought used from my local HD dealer). My pressures are 36 front & 40 rear.

Mike

 

My headstock bearings were loose when they were checked at 8000...could have happened before that, not allot of aggressive riding around here where I would have noticed. Did have a slight vibration in the front so I think it was that and a rotor that was a little warped.

We have bad roads here so Im sure that was a contributor.

 

You will get a lot of thoughts on this. I'm assuming no gravel/water, well tuned bike with no surges at certain parts of the torque/HP curve, and the bike checks out well with head bearings, throttle cables, wheels/tires in order, etc:

1. At your perceived higher speeds do you lean the bike more (tilting it to make the turn) or hang off (use your body weight to make the turn while keeping the bike upright)? Some use more "body english" at higher speeds, decreasing radius turns, etc. That can make a difference in feel and sensation at different speeds for some.

2. Do you roll on the throttle, hold throttle, or roll off the throttle at higher speeds or introduce braking into the mix?

3. Are you rigid in your body position at higher speeds or somehow reacting differently? At higher perceived speeds it is possible that a rider tenses up a bit and can "feel" a bit of difference.

Those are my thoughts. I hope they are somewhat helpful.

Best Regards,

Karl

 

Karl:

You may be on to something. The big sweepers were where I noticed/perceived the shimmy. These are the first high speed sweeping turns I have ever taken on the bike. I was definitely leaning my body more with the bike while turning. And, I was definitely more apprehensive about these turns and no doubt more rigid with my grip and arms. My first thought was loose spokes based on recent threads on this site.

After I first felt the shimmy, I tried to really evaluate what was happening with the bike and to judge whether I needed to abort the ride and limp home to diagnose the problem. Obviously, the bike felt stable enough to continue.

There seems to be no play in the steering head. And, the road conditions and asphalt were excellent. The tires look basically new. And they are inflated properly.

Perhaps my body position is poor and my hands and arms are just too rigid and tense in the sweepers...

Thanks Karl. I will take this in to consideration next time I go on this ride

Mike