Major Wobble at high speed - didn't expect it

Sorry Ferret, that's one thing I can't be accused of, pie diet sees to that.
It may be on this thread earlier, or not, but I took delivery of a new service bike in 1995, it was a ST1100 fresh from Sonic in the UK. My colleague also took delivery on an identical Bike at the same time and both came on Dunlop's, I think they were something like 458's but don't quote me on it. Before we could get out of the yard we were both directed to the M6 motorway where the IRA had decided to place charges on the gantries and pylons, just to keep us busy.
Both bikes were unrideable above 85 mph, taking up two lanes of the motorway with weave, I kid you not. The advice on the above video, which I watched in training did not help. Mudley Talker's advice did not translate to Honda weave.
Anyway the day came and went and neither of us died and the bikes were on Bridgestones for the next shift. They were both transformed and pretty much rock steady to a true 130 mph. Explain that away by weight, tyre pressures, worn suspension etc?
Upt'North.
 
I'm not denying that accidents occurred and people were injured or killed.

What I am saying is that if the view is that it was not fit for purpose for police use and that the police versions aren't significantly different from the one in my garage, then mine isn't fit for purpose either.

Edit: the 2007 test by Rider magazine showed the weave existed at 110 mph under certain loading conditions. Unfortunately I can't find that issue so I don't have access to the loading conditions which caused the weave.

There's no speed limiter which prevents the civilian version from traveling at speeds equivalent to the police versions.

If weight distribution and speed capability are taken off the table what prevents civilians from launching lawsuits against Honda for making an unsafe motorcycle?

Did Honda make any significant changes to the design after the well-publicized police accidents?

I'm not being argumentative here, I just don't think it's fair to say that Honda failed to supply a motorcycle fit for police use unless we're willing to also say it's not fit for civilian use when it's the same motorcycle.


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David, I'm no expert on the ST1300 handling issues, but they were real and reported here on a fairly regular basis and remember on occasions these were brand new bikes. The thing that does stick in my mind is that Honda became very tetchy about engine mount torque settings and perhaps this procedure changed or alterations were made to vehicles/tyres that we maybe aren't aware of.
Either way they still weave and wobble and yes all bikes do, it's physics apparently, either that or witchcraft.
It's a very salient point though that few bikes will be ridden as hard or as fast as service bikes. They have a hard life.
On a plus point on ST1300 handling they were a dream compared to K100's! Now they were just hateful.
Upt'North.
 
Sorry David, forgot to answer one question, is it fit for civvy use, I'd say definitely yes; although someone who's got one with a hinge in the middle may say different.
Upt'North
 
@Upt' North

The ST1100 had weave issues under certain conditions, but I can't say I ever figured out exactly why. Mine was stable at speed unloaded, but with some camping gear on the seat and rear tail rack it would tend to start weaving at 85mph. Not sure if it was the weight distribution difference (not much weight) or the aerodynamics change from having things sticking out sideways beyond my torso. Other riders reported the same issue, but many riders had no problems at all loaded or unloaded, so it varied by bike and rider. Coming from a sportbike to the ST I had the ride set relatively firm compared to stock. Then as I got older and took some of the preload out of the rear shock, it seemed to cure the weave.

@David

With pretty much the same camping gear load on my FZR1000, I took it up to 167mph indicated in the Nevada desert one time without any issues at all, and many other 100+ excursions over the years. That's a much lighter bike than the ST, so the added weight was a higher percentage of the bike weight. Most bikes have a pretty wide range of 'acceptable' variation from stock weight distribution before you'd expect stability issues to arise. The ST1300 appears to be either more sensitive than most in weight distribution, or even has potential stability issues in stock form. I've never owned one, so I have no opinion either way, but the fact that it has its own term that can be googled (Pan Weave) would suggest the problem is not limited to a few people who did something stupid that Honda couldn't have expected.
 
Dwalby. Yes my 11 is rock steady at all speeds and all loads, from one up with worn tyres to two up with luggage etc. But like you say others can be pigs.
Upt'North.
 
How is it that the performance of bikes (ST11s and ST13s) made on an assembly line can vary so much from bike to bike?
I suggest that it's everything external to the bike.


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DavidR8 said:
How is it that the performance of bikes (ST11s and ST13s) made on an assembly line can vary so much from bike to bike?
I suggest that it’s everything external to the bike.
Click to expand...

google "production tolerances"
 
DavidR8 said:
How is it that the performance of bikes (ST11s and ST13s) made on an assembly line can vary so much from bike to bike?
I suggest that it’s everything external to the bike.


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Click to expand...
big differences between 13 and 11. 1100= 27.3 degrees rake and 1300 is 26,,, front forks are heavier on the 1300 45mm where 1100 have 41 and 43mm. 1300 is 20 lbs lighter (both with with abs) weave happens even to motogp racers it can happen to all bikes see https://motorbikewriter.com/avoid-tank-slapper/ and see this video [video=youtube;as3lyruGObc]https://www.youtube.com/watch?time_continue=5&v=as3lyruGObc[/video]
 
Is it possible that the wobble started because you suddenly backed off the throttle?

If so then back on the throttle will straighten things out and then slowly back off the throttle to slow down. NEVER hit the brakes!
 
Let's be honest about this, there is far too much going on, from a scientific point of view, for most of us mere mortals to be able to analyse this. If the mighty Big H couldn't sort it and just played dumb then us armchair engineers aren't going to be able to work it out.
My thought is that there are so many variables, from aerodynamics to weight distribution, through tyre pressure/choice and external environmental conditions (wind and slipstreams), that it has been impossible to fix. It also seems to manifest itself at "illegal" speed, so therefore none of us are likely to experience it, right? :rolleyes:
I often wonder whether that is why Honda never sought to improve/upgrade/develop the Pan.
 
DavidR8 said:
Did Honda make any significant changes to the design after the well-publicized police accidents?
Click to expand...

I haven't seen anything that explicitly addresses the high speed weave that some bikes seemed to display. But there is an addendum to the 2002/2003 service manual which includes modified procedures for the 2002/2003 bikes and distinguishes these from a different setup for the 2004 bikes. These relate to engine mounting and swinging arm installation.
 
jfheath said:
I haven't seen anything that explicitly addresses the high speed weave that some bikes seemed to display. But there is an addendum to the 2002/2003 service manual which includes modified procedures for the 2002/2003 bikes and distinguishes these from a different setup for the 2004 bikes. These relate to engine mounting and swinging arm installation.
Click to expand...

Wasn't the first report of the weave in 2007?
I wonder what they were fixing/changing with the 2003-2004 changes.
There are no recalls are there?


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I was merely pointing out that the addendum to the shop manual describes a modified set of procedures. The 2002/3 swing arm pivot arrangement is different from the one on the 2004 model. The arrangement described and illustrated in the addendum for the 2004 model seems to be the same as the one on my old A6 model and my current 2013 built A9 model.
Whether or not the weave issue and the modified procedures are related I don't know. As I said - I haven't seen anything that explicitly addresses the high speed weave issue.

Pc Shreeve had his fatal accident in November 2005, but according to reports in the UK press, eg here, officers had reported problems since January 2003. The inquest was reported in 2007.
 
DavidR8 said:
Ahh thanks for clarifying that Jeff.
Is it safe to say that from model year 2004 the swing arm pivot was changed?
Click to expand...

I'm not sure about that. It would seem so, but I took a look at the fiches a while back. For UK models, the 2004 and 2006 show both pivot bolt arrangements. The earlier pivot is not shown on the 2008 fiche. However, my 2006 model had the later pivot.

I was trying to determine whether the swing arm pivot gave an indication to the year of the bike - it being a very obvious difference when seen on a photograph, but I couldn't be certain.

John
 
The P models have different swing arm pivot mounts then civ models. At least on this side of the pond.

Never heard the 110 mph listed before, but can confirm it. With topbox on, no pre-load, no passenger you hit 111 (gps) and the back starts to weave, 112 it weaves more, gently let off the throttle and it settles down, roll on the throttle and it's back. But change a setting, pull off the box or fill in the void and it's fine to speeds of... umm... faster.

Hmm... haven't checked for the weave since I put a stiffer spring in the tail... wondering...
 
T_C said:
The P models have different swing arm pivot mounts then civ models. At least on this side of the pond.

Never heard the 110 mph listed before, but can confirm it. With topbox on, no pre-load, no passenger you hit 111 (gps) and the back starts to weave, 112 it weaves more, gently let off the throttle and it settles down, roll on the throttle and it's back. But change a setting, pull off the box or fill in the void and it's fine to speeds of... umm... faster.

Hmm... haven't checked for the weave since I put a stiffer spring in the tail... wondering...
Click to expand...

I'd love to see photos of the pivot on a p model.


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jazzkat said:
Let's be honest about this, there is far too much going on, from a scientific point of view, for most of us mere mortals to be able to analyse this. If the mighty Big H couldn't sort it and just played dumb then us armchair engineers aren't going to be able to work it out.
My thought is that there are so many variables, from aerodynamics to weight distribution, through tyre pressure/choice and external environmental conditions (wind and slipstreams), that it has been impossible to fix. It also seems to manifest itself at "illegal" speed, so therefore none of us are likely to experience it, right? :rolleyes:
I often wonder whether that is why Honda never sought to improve/upgrade/develop the Pan.
Click to expand...
Wow an honest and fair minded thought !!!! Watch MotoGP they (with all their engineers and money still get a weave) not all the time but a condition happens to cause it. Think about it, take a gyroscope and spin it, sometimes its good but it just takes the smallest thing to throw it off and it wobbles. On a bike you have two gyroscopes. Just because you have not experienced the weave before doesn't mean you have hit the condition the can cause a weave.
 
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