Stock Suspension: Issues and Adjustments

[Jiggles]

I used to use the alignment marks but then I've heard that its not accurate.

Just checked them and they are equivalent on both sides.

I'll try the no hands thing tonight and see if I feel anything. Actually though now that you mention it, I have sort of noticed something when I am going straight. I say sort of because half the time I think I'm imagining it I almost feel like to go straight the bike is slightly angled and I also have to "hold" it to go straight. I think I am pushing on the left bar with a small amount of force to keep it going straight. I'll test it and post back here

 

[afm199]

I suspect that 50 series rear is part of the problem.

 

[Jiggles]

I suspect that 50 series rear is part of the problem.

Think so huh? I actually read a review that said switching to a different rear stopped it from wanting to turn in like it does so that just might be the case. Does anyone need an aborted tire?

I tried the no hands thing last night and my bike does drift off to the right which I think falls in line with the extra pressure I apply on the left bar to keep it straight

 

[rapidrobbie]

Its supposed to pull right slightly due to the crown of the road.You can try it in a big parking lot,no crown,just sloped for drainage

 

[Jiggles]

Its supposed to pull right slightly due to the crown of the road.You can try it in a big parking lot,no crown,just sloped for drainage

I tried it on the flattest road I could find and it still did it. And when you factor in the noticeable pressure I have to apply to the left bar in order to go straight it makes sense. This is a symptom of a misaligned rear or my poopoo tire size? What is a good tire size to switch to to eliminate this issue?

As a comparison, I got back on my 2fiddy for the first time in a month and omg it rides so nice. Turning is just effortless. I took my hands off the bars in a turn and it held the line. That is what my 1000 should be doing

 

[Ironbutt]

I tried it on the flattest road I could find and it still did it. And when you factor in the noticeable pressure I have to apply to the left bar in order to go straight it makes sense. This is a symptom of a misaligned rear or my poopoo tire size? What is a good tire size to switch to to eliminate this issue?

As a comparison, I got back on my 2fiddy for the first time in a month and omg it rides so nice. Turning is just effortless. I took my hands off the bars in a turn and it held the line. That is what my 1000 should be doing

Just ride it harder..

 

[tuxumino]

misaligned triple clamps?

 

[Jiggles]

Just ride it harder..

 

[KnifeySpoony]

Have someone else ride the bike and see if they feel it.

 

[afm199]

Here's a hint. change nothing but lean further forward before you start a turn, try to get more weight on the front end and see if that improves steering. My contention is that improper sag and that POS rear tire have the bike front high and rear low, which makes for very slow steering.

 

[Jiggles]

Here's a hint. change nothing but lean further forward before you start a turn, try to get more weight on the front end and see if that improves steering. My contention is that improper sag and that POS rear tire have the bike front high and rear low, which makes for very slow steering.

Hey I'll try it but the turn in feeling is less severe when I am accelerating so I think loading the front would make it more severe.

I don't have a front stand so I won't be able to adjust the sag in the front right? I'm sure it's something rob at evolution will be able to do for me though.

What size tire should I switch to, 190/55? Or something else?

 

[afm199]

Hey I'll try it but the turn in feeling is less severe when I am accelerating so I think loading the front would make it more severe.

I don't have a front stand so I won't be able to adjust the sag in the front right? I'm sure it's something rob at evolution will be able to do for me though.

What size tire should I switch to, 190/55? Or something else?

Try it. Don't overthink this. Yes 190 55.

You can get someone to help and do the sag yourself easily.

 

[Ol' Gravy Leg]

Jiggy, what you are describing is called wheel flop. Wheel flop refers to steering behavior in which a bicycle or motorcycle tends to turn more than expected due to the front wheel "flopping" over when the handlebars are rotated. Wheel flop is proportional to the trail and a function of the steering angle.

I experienced this when I change to a 70 series front from stock 65 on my 636. The additional circumference increased the trail and also the wheel flop.

So, I'm actually siding with afm on this one. An improper sag compounded by a 50 tire can make your front ride too high, relative to the rear thereby increasing the trail (and flop).

First things first. Learn to set that dang sag!

http://www.sportrider.com/tech/146_0308_set_your_static_sag/viewall.html

Ride it. Then check out Dave Moss's videos to see how to set your rebound and compression (he does a good job with former; the latter is more trial and error/taste).

One thing still disturbs me is the lack of symmetry with respect to turning. Nevertheless, set the sag.

[edit: you don't need stand to set sag.]

 

[Jiggles]

Jiggy, what you are describing is called wheel flop. Wheel flop refers to steering behavior in which a bicycle or motorcycle tends to turn more than expected due to the front wheel "flopping" over when the handlebars are rotated. Wheel flop is proportional to the trail and a function of the steering angle.

I experienced this when I change to a 70 series front from stock 65 on my 636. The additional circumference increased the trail and also the wheel flop.

So, I'm actually siding with afm on this one. An improper sag compounded by a 50 tire can make your front ride too high, relative to the rear thereby increasing the trail (and flop).

First things first. Learn to set that dang sag!

http://www.sportrider.com/tech/146_0308_set_your_static_sag/viewall.html

Ride it. Then check out Dave Moss's videos to see how to set your rebound and compression (he does a good job with former; the latter is more trial and error/taste).

One thing still disturbs me is the lack of symmetry with respect to turning. Nevertheless, set the sag.

[edit: you don't need stand to set sag.]

Ok cool so I don't need a stand. I'll try dicking around with it and see of I can get it feeling better. From what I can tell right now I have too much sag and I'd want to go about lossening the preload yea?

 

[Ol' Gravy Leg]

Ok cool so I don't need a stand. I'll try dicking around with it and see of I can get it feeling better. From what I can tell right now I have too much sag and I'd want to go about lossening the preload yea?

We'll that's what we are figuring out. We can't make any proper diagnoses until the sag it set properly, both front and rear.

For now just do a quick and dirty adjustment.

Start with a ziptie on the fork just below the seal. Measure the distance from a fixed spot near the brake caliper.

Sit on the bike like you normally ride, both feet on pegs and bike balanced upright. (Hold onto something.) Measure the position of ziptie again. The difference is how much the ziptie moved. This is your sag. It should be in the neighborhood of 30mm (+-5mm).

You'll repeat this excercise with the rear and a piece of string. You can do it alone if you are cleaver, but it is a lot easier with a friend doing the measuring. Rear sag should be around 25mm.

If you have too much sag, you want to increase the preload and vice-versa for both.

Then ride it and report back. It could also be that you have way too little rebound damping in the front or too much compression (or, somehting else entirely). However, we won't know until you set the sag.

There is more to setting up a suspension properly, but this will get you pointing in the right direction. Suspension/geometry have so many variables that you can just muck with one thing until it feels right. You have to be a bit more methodical to start with.

 

[Jiggles]

Alright cool, I'll try an get it measured this week when I have some time and it isn't raining

 

[afm199]

We'll that's what we are figuring out. We can't make any proper diagnoses until the sag it set properly, both front and rear.

For now just do a quick and dirty adjustment.

Start with a ziptie on the fork just below the seal. Measure the distance from a fixed spot near the brake caliper.

Sit on the bike like you normally ride, both feet on pegs and bike balanced upright. (Hold onto something.) Measure the position of ziptie again. The difference is how much the ziptie moved. This is your sag. It should be in the neighborhood of 30mm (+-5mm).

You'll repeat this excercise with the rear and a piece of string. You can do it alone if you are cleaver, but it is a lot easier with a friend doing the measuring. Rear sag should be around 25mm.

If you have too much sag, you want to increase the preload and vice-versa for both.

Then ride it and report back. It could also be that you have way too little rebound damping in the front or too much compression (or, somehting else entirely). However, we won't know until you set the sag.

There is more to setting up a suspension properly, but this will get you pointing in the right direction. Suspension/geometry have so many variables that you can just muck with one thing until it feels right. You have to be a bit more methodical to start with.

Actually the sag figure should be from the fork or rear end fully extended to compressed with your weight on it. The bike with no one on it will sag 5-15 mm..

 

[Ol' Gravy Leg]

Actually the sag figure should be from the fork or rear end fully extended to compressed with your weight on it. The bike with no one on it will sag 5-15 mm..

You're right, now that I think about it. I was just spouting off from the top of my head. Thanks for the correction.

[edit: actually 30mm~1 inch. and that seems right. I'll look it up.]

[edit2: I defer to Ernie. Indeed from full extension to load with rider=static sag. So, have a friend help you, Jiggles.]

 

[afm199]

You're right, now that I think about it. I was just spouting off from the top of my head. Thanks for the correction.

[edit: actually 30mm~1 inch. and that seems right. I'll look it up.]

[edit2: I defer to Ernie. Indeed from full extension to load with rider=static sag. So, have a friend help you, Jiggles.]

I never spout off I just spew constantly.

 

[Jiggles]

I run 30-23 on a liter bike on the track.

The 190/50 is an abortion of a tire. Get a 55 series.

An update! The problem is much much better now but not entirely gone. I took the bike into evolution and had the suspension set up. Funny thing is that the adjustments I had made were pretty much dead on. The sag was good on the front and back, wheels were perfectly aligned, but I still had the problem. He made an adjustment to the rebound damping (I think) and when I rode away it felt a little better.

So then I headed over to the dealer to see where my Givi case was and if they knew anything about this weirdness. Well one of the guys in the service shop knew exactly what the problem was, that 50 rear tire. So I got an S20 190/55 and it feels much much better. I'll have to test it out in the twisties but the right side feels almost perfect and the left is still wanting to stand up but requires less force.

It seems that raising the rear is helping to solve (or mask???) the problem. I may up the preload some more tomorrow on the rear to see if that helps.