[NHViffer]

Went out on the Daytona Saturday and have a suspension tuning question for any of you tuning pro's ...

This is the first bike that I've had that offers me full adjustable front & rear suspension. I got baseline settings from a Triumph owners website for my weight, which seemed to be a pretty good place to start. I think that I have a good handle on the front settings and these seem easier to me to "feel", but I think that the rear has something off.

I was leaning pretty hard into a corner that had a series of decent bumps in the middle of it (not frost heaves, but larger than ripples). About 1/2 way through the bumps the bike started what I can best describe as a leaned over "wabble". I let off the throttle a bit and totally blew the corner (actually crossed the yellow line - yikes!). It was a corner that I could see through with no problem so there was no issue with oncoming traffic.

My question is whether playing with the rebound or compression damping can solve this? I do not have a feel for how the rear will respond to changes in these settings.

I will admit that for the amount of lean that I had going on, my body was probably not far enough off to the inside (lazy previous VFR rider ). I don't yet have knee pucks and don't think that I should have them for the street anyway, because I would likely try to use them.

BTW - I had to back off the front rebound damping from the setting that I went to from the triumph site because the front wheel was getting very loose feeling even driving of turns with moderate throttle. Almost feeling like it wanted to start a tank-slapper. Changing the rebound just one turn seems to have solved this.

[stoinkythepig]

I'm by no means an expert but you should start with static sag before changing any damping characteristics. If the suspension is topping out or bottoming out in corners it will wallow like a bastid. Proper static sag (assuming the springs are sized correctly) will keep the suspension it's "sweet spot" under most conditions.

[g®eg]

Did you download the static sag excel sheet Bob posted to the NTSR list?

That would be a great place to start...

[NHViffer]

Yes, I have not done the static sag yet because it requires another person to help do it. I guess that I am just trusting the settings for my weight from that Triumph forum. Since my saturday ride I have backed off the front preload by 1/2 a showing ring. I have also finally gotten the lock nut loose on the rear spring and added more preload in the back.

I don't understand why the factory settings are always for some 150 lb light weight. Me, loaded tank bag and garb are easily over 200 pounds (which converts to 14.3 stones, since I am adjusting a UK bike ).

I guess that I need to re-run that road....darn, the things we have to do in the name of science.

[NHViffer]

Originally posted by T-595 Greg
Did you download the static sag excel sheet Bob posted to the NTSR list?

That would be a great place to start...

I did see that, but have not yet downloaded it. The issue is not so much with the calculations/math, but with attempting to do it by myself. Does anyone know any tricks to doing this alone?

[stoinkythepig]

Originally posted by NHViffer
I did see that, but have not yet downloaded it. The issue is not so much with the calculations/math, but with attempting to do it by myself. Does anyone know any tricks to doing this alone?

Can't do it alone. Get two friends to help, one to balance and one to lift up and push down on the suspension to reduce stiction induced errors. The friend that lifts and pushes can also make the measurements.

[NHViffer]

Originally posted by stoinkythepig
Get two friends to help

Two friends - that's near impossible

Since Stoneman works in Manchester, maybe I can get him to stop by my place after work one day - he can be the pusher

[stoinkythepig]

I would like to re-set mine since the springs seem a little softer since I last set it. Perhaps we could do both bikes some time? I'm not far from Manch Angeles

[NHViffer]

I know Raymond somewhat, also. I even need to go there to see a friend of mine soon. Are you available this weekend, whether we do it Manchester or Raymond? I have Friday off this week, and also the weekend, but Sunday is probably not too good since it's Easter.

I have a single car garage for the motorcycle, snowblower, bikes, etc... It is great for working around one bike at a time.

I probably have any tools that we might need also (just bought a spanner for the rear shock nuts).

What's your space/tools situation?

[stoinkythepig]

Space is not a problem at my house. I have a two car garage and plenty of tools. I'd prefer to do it there anyway.

This weekend will be OK. I'm in the midst of finishing an addition on my house and a suspension adjustment session would be a welcome break from that. Does not take long to do. I'm sure my wife will give me the time off for good behavior.

[Degsy]

If what you mean by this is that the rear is bouncing lazily on an osscillating kind of motion, then you are looking at:

1. Not enough preload
2. Too much ride-height (probably not adjustable on that bike), although you could raise the pront a little to compensate)
3. Not enough compression damping (rear wheel is compressing too fast/too far and when you hit the next bump the tire can't follow the bump's contour properly).

When you adjust suspension, only adjust ONE thing at a time, and only by a small amount each time.

YMMV

Just my opinion

Degsy

[Honclfibr]

Viff, if you need another hand, I'd be willing to help. I'm down in Derry, not more than a stone's throw from Manchester or Raymond. I've never adjusted a suspension before, so I'd be interested to watch how it is done.

[NHViffer]

Guys, sorry to leave you hanging on this.

I probably wont make it for sag adjustment this weekend. From what I can tell, the adjustments that I made last week are excellent. No complants right now, but I still need to try the problem corner.

I'll be out finishing off my first 500 miles today, then doing the 500 mile stuff later today and tomorrow.