Front & rear suspension settings

[21QUEST]

Originally Posted by RingDing

Yes you're right in that it confirms the amount of rider sag to set for. However, your method of measurement (included below cause this is getting confusing!) does not give rider sag, or static sag for that matter. It gives the difference between the two. That could, potentially, be dangerous as all you are doing is trying to set some degree of sag at some point in the suspension travel. Your reference, which is the static sag, could be anything. It is extremely unlikely to be an issue (and won't be if you already have the correct spring rate) but if you are only going to set rider sag then you should still do it with reference to the UNLOADED suspension length. That is the standard method of measurement, as the article bears out.

As for the rest of your disagreements with 21Quest... I'm keeping out of it! :lol

Thank you RingDing. Maybe now someone else has pointed that out PeterM can begin to do things the right way. If only he'll admit to his mumbo jumbo .

With reference to the highlighted bit , it's okay you are welcome to join .

Cheers
Ben

PS: Lol. Another thing for you(PeterM) to think about is this question. You talk about adequate springs so how do you arrive to that point(apart form the collective reasearch blah , blah.

Hint: I believe the guy leading the thunderbike series(so must be fast) runs springs softer(lower rate) than a lot of tuners would probably recommend in mind for racing. He'll correct me if I'm wrong.

Okay I'm being a bit mischievous but I'm only trying to make you think.

Originally Posted by RingDing

Yes you're right in that it confirms the amount of rider sag to set for. However, your method of measurement (included below cause this is getting confusing!) does not give rider sag, or static sag for that matter. It gives the difference between the two. That could, potentially, be dangerous as all you are doing is trying to set some degree of sag at some point in the suspension travel. Your reference, which is the static sag, could be anything. It is extremely unlikely to be an issue (and won't be if you already have the correct spring rate) but if you are only going to set rider sag then you should still do it with reference to the UNLOADED suspension length. That is the standard method of measurement, as the article bears out.

As for the rest of your disagreements with 21Quest... I'm keeping out of it! :lol

No probs with that mate. As you've worked out I'm coming at this from already having the appropriate springs fitted. Whenever anyone asks a question about their suspension on the Aust site we always point them in the direction of getting the right springs fitted first and then work from there. An error on my behalf to assume that the same approach is always taken here but since it's a different site then I should've been more particular.

Originally Posted by 21QUEST

Thank you RingDing. Maybe now someone else has pointed that out PeterM can begin to do things the right way. If only he'll admit to his mumbo jumbo .


PS: Lol. Another thing for you(PeterM) to think about is this question. You talk about adequate springs so how do you arrive to that point(apart form the collective reasearch blah , blah.

Hint: I believe the guy leading the thunderbike series(so must be fast) runs springs softer(lower rate) than a lot of tuners would probably recommend in mind for racing. He'll correct me if I'm wrong.

Are you for real? The "right way". Get stuffed you sanctimonious wind bag. Call it speaking in a different dialect if you like but if the same question was posed on the Aust site you'd get an answer like mine. As i said in my response to RingDing, I will have to be more mindful of the conventions here to prevent sagas such as this.

Most suspension companies have poured significant funds into calculating what springs are appropriate for riders of a given weight for a given bike. These people often have substantial experience in such things and so I hope you'll excuse me if I defer to their expertise.

Since you've decided to take things to the racetrack well then.......Each rider has a different style and preference that tends to dictate how their bike is set up. Throw a leg over Troy Bayliss's bike and then compare to Lorenzo Lanzi, or any other two teammates in the world and you will likely find the bikes set up differently. These are people with a much higher level of skill than your average road rider and therefore do things that work for them.

Yes, softer than what some may recommend works for him, great. Bully for him. We are talking about people riding on the street with not the same skill level and we have no idea on their level of expertise or skill. Therefore it is logical to use the path of best fit for general advice.

[21QUEST]

Originally Posted by PeterM

Are you for real? The "right way". Get stuffed you sanctimonious wind bag. Call it speaking in a different dialect if you like but if the same question was posed on the Aust site you'd get an answer like mine. As i said in my response to RingDing, I will have to be more mindful of the conventions here to prevent sagas such as this.

Most suspension companies have poured significant funds into calculating what springs are appropriate for riders of a given weight for a given bike. These people often have substantial experience in such things and so I hope you'll excuse me if I defer to their expertise.

Since you've decided to take things to the racetrack well then.......Each rider has a different style and preference that tends to dictate how their bike is set up. Throw a leg over Troy Bayliss's bike and then compare to Lorenzo Lanzi, or any other two teammates in the world and you will likely find the bikes set up differently. These are people with a much higher level of skill than your average road rider and therefore do things that work for them.

Yes, softer than what some may recommend works for him, great. Bully for him. We are talking about people riding on the street with not the same skill level and we have no idea on their level of expertise or skill. Therefore it is logical to use the path of best fit for general advice.

Like I said in the on the thread , we just have to agree that you are the man.

Peace
Ben

Quit being patronising. Would it kill you to concede that you understand what I'm saying and the intent behind it?

Originally Posted by PeterM

Quit being patronising. Would it kill you to concede that you understand what I'm saying and the intent behind it?

The original power asked about setting the suspension on, presumably, a stock bike. Where did he ever mention having the correct springs?

You made alot of assumptions, why get anoyed when this was pointed out?

Originally Posted by Flamin_Squirrel

The original power asked about setting the suspension on, presumably, a stock bike. Where did he ever mention having the correct springs?

You made alot of assumptions, why get anoyed when this was pointed out?

I thought the same, poor lad only asked if he should adjust his preload because he was going to put some soft luggage on his bike :P He is probably on his holidays by now

[21QUEST]

Ok , not to carry on what appears to be a ****ing contest but I decided to revisit one more time.
People interested or with indeed better knowledge are welcome to point out to me where I've got it wrong with regards to PeterM posts quoted below.

Particular attention should be given to the highlighted bit

Originally Posted by PeterM

Right then. Do the maths for the differences in the figures quoted for static and rider sag. Lo and behold it comes pretty close to the 25-30mm difference I gave in the first place. Still with me? Understanding are we?

The reference I made to 'sag' was to refer to the difference between static and rider sag.

The figures I'll be working with have be taken from two different web sites. GOSTAR RACING AND RACETECH.

Note that we are assumming that the springs are correct as worked out by the Racetech spring calculator. It is therefore it is safe to also assume that the numbers for Bike and Rider sag should be within the general acceptable limits.

For sake of clarity/simplicity an average of the range of figures given would be used ie that of upper and lower limits.


RACETECH
Front Rider Sag 30-35= 32.5 average Front Bike Sag -no figures given

Rear Rider Sag 30-35=32.5 average Rear Bike Sag 0-5=2.5 average



GOSTAR-RACING
Front Rider Sag 35-48=41.5 average Front Bike Sag 25-30=27.5average

Rear Rider Sag 30-40=35 average Rear Bike Sag 5-10=7.5 average


Initial post which has since been clarified above(highlighted) was

Originally Posted by PeterM

From the bike sitting there under it's own weight to you being on it, both feet on the pegs, the suspension should settle 25-30mm for general road use. Obviously it is very handy to have at least one other person available to help with all this.

If we apply the above logic , you get

REAR
Racetech=32.5mm(rider sag) minus 2.5mm(bikebike sag)=30mm

Gostar-racing=35mm(rider sag) minus 7.5mm(bike sag)=27.5mm

At this point point you think yep nothing wrong with the above ie The difference in both case applying said method are quite close to the general acceptable range. ..but hold on a sec as we are yet to do the front.

Front
Racetech=N/A as no bike sag given
Gostar-racing 41.5mm(rider sag) minus 27.5mm(bike sag)=14mm

I think it is clear to see that the difference we got using the above logic for the rear which appears to be correct was purely by luck and the figures for the front ie 14mm is so far out that it is more than just unlucky.

To add to what I've been trying to say below is a piece from the traxxion dynamics site. Click on the link for more

Originally Posted by TRAXXION

4. Setting the Sag:

First you need a fully extended measurement. I've found that the only way to get this measurement with any consistency, is to make sure the front wheel actually leaves the ground slightly. You can do this with a jack under the pipes or a couple of helpers. Measure the exposed area of the fork slider. On a conventional fork, this will be from the bottom of the lower triple tree to the top of the dust seal on the slider. For an inverted fork, this will be from the dust seal down to the top edge of the axle clamp (See Figure 6). Record this measurement on your log sheet. Push down on the fork hard three times to settle the suspension. Now measure the same two points again. Subtract this number from the fully extended number to get your "bike sag" or "free sag" number. Finally, you get on the bike and push down three more times, while a friend balances the bike. Have your friend with the tape take the final measurement. Subtract that from the fully extended number to get your "rider sag". The measurement we are looking for on the front fork is 35mm. If your spring is of the correct rate, the static sag should be about sixty percent of the rider sag, or about 20mm. The front fork has to have a great deal of static sag so that the front wheel may move down into a hole as well as over a bump. If your fork has too much sag, turn the preload adjuster in. If you don't have preload adjusters, then you will have to remove your fork spacers and cut longer preload spacers. Adjust in five-millimeter increments. These numbers and this method represent a guideline for you to get a starting point.

Again using PeterM logic , the difference in the numbers given for the front bike and rider sag is 15mm which is nowhere close to 25-30mm.

http://www.traxxion.com/technical.forkspr.install.shtml

The only way that logic would work to get a true rider sag of 25mm is if you are basically running zero bike sag which if followed logically would mean the spring is the wrong rate.
Therefore even assumming that one has chosen the correct spring rate in the first place, it remains incorrect.

As previously mentioned , please feel free to point out where I've got it wrong.




Cheers
Ben

Originally Posted by Flamin_Squirrel

The original power asked about setting the suspension on, presumably, a stock bike. Where did he ever mention having the correct springs?

You made alot of assumptions, why get anoyed when this was pointed out?

Please check out my first response. I mentioned that the stock springs were most likely too light for him.


Wheelnut, you're right, hope he sends a postcard and has a safe and enjoyable trip.


Ben, I commend you on your research but I can assure you that it isn't dumb luck that the figure for the rear rider-static sag figure was correct.

Regarding the front, yes you'd want that down to 14-15mm for the track, no argument there. It's interesting (but not unexpected) to see Gostar-Racing and Traxxion give different figures though, no doubt personal preference of whever wrote the notes. Applying that to the road isn't really appropriate though is it? I wish roads had a surface as nice as the track but that's not going to happen. That extra little bit could come in handy on a less than perfect road. This is how it was explained to me when my bike was set up for me by a suspension professional who does both road and track work. That's why I've been a bit dogged here, actually working with someone to get the right setup rather than purely going from the written word without any interaction was very helpful and informative.

As always, it will end up coming down to rider preference though.

[21QUEST]

Originally Posted by PeterM

Ben, I commend you on your research but I can assure you that it isn't dumb luck that the figure for the rear rider-static sag figure was correct.

Regarding the front, yes you'd want that down to 14-15mm for the track, no argument there. It's interesting (but not unexpected) to see Gostar-Racing and Traxxion give different figures though, no doubt personal preference of whever wrote the notes. Applying that to the road isn't really appropriate though is it? I wish roads had a surface as nice as the track but that's not going to happen. That extra little bit could come in handy on a less than perfect road. This is how it was explained to me when my bike was set up for me by a suspension professional who does both road and track work. That's why I've been a bit dogged here, actually working with someone to get the right setup rather than purely going from the written word without any interaction was very helpful and informative.

As always, it will end up coming down to rider preference though.

For Petes sake I give up. Frankly we have a better chance of Skippy being able understand the concept and point.

You are a complete buffoon with the processing power of an amoeba and more stories than on Jackanory.

At this juncture I will leave you to wallow in your ignorance whilst basking in the glory of your perceived knowledge and understanding.

Peeps will be well advised to ignore your moronic trash.

Cheers
Ben

Don't worry you can have the last word