Fender mounting

[hogv8]

Using Aldan 350LB rear shock springs how close do you think one could safely mount a rear fender from the rear tire without fear of the fender hitting the tire under normal riding conditions ?

Jack

[502wingman]

Jack,
I guess there is no exact mesurement because this depends all on the weight you are carrying, the preload of the springs, road conditions etc. Last summer I have seen some bikes from Denmark with fenders 1/2" above the rear tire. The fender is fixed to the swingarm, so this works in any situation. May be somebody here took a picture.
Peter

[502wingman]

Not a good picture of the fender to see how it is fixed etc. and there were better ideas too. But thats the only one I seem to have.

[AR]

... the preload of the springs

Haha...sorry Pete, but the idea of "pre loading" these springs always makes me laugh. Call me a bush engineer but when we wind these springs up we preload SQUAT!

All the winding up we do is lengthen the overall shock assembly...nuthin more.

[hogv8]

Thanks Peter , I'm not to concerned with the 2" of clearance with the 350 Lb . springs . I weigh 225 lbs and Cheryl weighs 135 lbs . She has her own Harley and very seldom rides with me . I did make up a set of rubber bump stops out of Hockey puck rubber spilt on one side , 3/4 " thick that I can slide in between the spring coils and around the center shaft if I need to that will reduce the shock travel when Cheryl rides with me if I do have a problem .

Rob , please explain your theory . I don't understand how cranking up the spring pressure can make the shock longer ???? Harder riding and less compression but not a longer shock .

Jack

[AR]

Rob , please explain your theory . I don't understand how cranking up the spring pressure can make the shock longer ???? Harder riding and less compression but not a longer shock .
Jack

Ok Jack,

you just opened my pandoras box...

This is from the factory manual...it alerts the owner that the shocks are preset for 50/50 extension compression.

This is how I see what happens when we 'wind up the spring' supposedly preloading - but in reality the sping stays the same length and we are reducing the available "extension" and increasing the available "compression". Like I said, spring stays the same length, overall shock length is increased, and ride height is increased also.

..and as supporting evidence I offer this extract from Olduns / Wags records of what the Factory and Aldan do when asked to assist with a 'too soft' ride. They both change the springs to stiffer versions which is an odd thing to do if all you have to do is 'preload' by winding the spring up a little.

The only reason we think we are preloading is because we been told by others but until someone draws me a sketch that proves otherwise I'm telling you its bullshit.

[502wingman]

Jack, thats a great idea, just in case the setting is too soft or you hit a "surprise" bump.

Rob, I dont believe it. From my own experience I can tell you that, the more you compress the the springs, the harder it becomes to compress them more (i.e. give it another turn with the adjuster tool)

Peter

[AR]

Jack, thats a great idea, just in case the setting is too soft or you hit a "surprise" bump.

Rob, I dont believe it. From my own experience I can tell you that, the more you compress the the springs, the harder it becomes to compress them more (i.e. give it another turn with the adjuster tool)

Peter

Yeah I know Pete but as nice as you are along with 99% of the population - have been brainwashed Its true! Can you please explain me why/how you think the spring gets compressed when you wind it up? There is another geometry factor that might explain it but you guys will might think I'm more than just a little nutjobbie....just remember its my right as a rebel to question convention here dudes!!!... I'm begging someone to put me out of my misery here its been whirring around my head non stop for years mixed up with all the fuggen Boz Scaggs songs from the 70's..... you should see it in there man

[hogv8]

Rob , there's a simple way to test your theory . Jack up the bike to take the pressure off the shocks , remove the bottom bolt , back off the adjuster rings until the spring is free { no Tension } , measure shock length eye to eye and it will be about 13 1/2" . Now tighten the adjuster rings to put whatever amount of pressure on the spring that you want to and remeasure from eye to eye and it will still be 13 1/2" . The shock will definitely be harder to compress but that 13 1/2 " from eye to eye won't change unless I'm really missing something here .

Jack

[hogv8]

Here's a test I was thinking about trying as far trying to determine the shock/swingarm travel . Jack the rear of the bike up so the rear wheel is off the ground , unbolt the bottom of the shocks and remove the springs completely . rebolt the shocks and using 2 ratchet straps one on each side around the frame and swingarm and ratchet the swingarm up to compress the shocks to the max against the rubber bump stop to see how much fender to tire clearance there is if any . The only thing that worries me is putting too much stress on the rear section of the frame or damaging the seals in the shocks . Anyone have an opinion on this ??

Jack

[AR]

Here's a test I was thinking about trying as far trying to determine the shock/swingarm travel . Jack the rear of the bike up so the rear wheel is off the ground , unbolt the bottom of the shocks and remove the springs completely . rebolt the shocks and using 2 ratchet straps one on each side around the frame and swingarm and ratchet the swingarm up to compress the shocks to the max against the rubber bump stop to see how much fender to tire clearance there is if any . The only thing that worries me is putting too much stress on the rear section of the frame or damaging the seals in the shocks . Anyone have an opinion on this ??

Jack

Is there a way you could set up a 'tell tail' as we say in building that will allow you to test the compression/travel you experience in the real world. Something mounted under the fender that wears or disintegrates to measure how close the tire gets to the fender. Like a lump of 'plasticine' or putty or something. Real life impact from road surfaces and tire deformation will no doubt be different from the lab results. What do you think Jack?

Oh yeah, I think I'll be able to jackup my bike and test out my shock length theory sooner than I wanted , I think I got a dose of the WB's.

[hogv8]

Rob , one test that I have tried is with the fender mounted 2" above the tire I placed a ball of modeling clay between the tire and the fender then Cheryl and I both sat on the bike and simultaneously we bounced up and down on the seat as hard as we could and then measured the clay thickness . It measured about 3/4" which means us bouncing simultaneously on the seat as hard as we could compressed the shocks 1 1/4 " . How this compares to normal road conditions I'm Not sure .

Another test was to place clay between the rubber bumper stop and the shock body and bounce and it also compressed the clay to about 3/4" . I'm fairly confident that 2" fender to tire clearance is sufficient but the real test will be on the road with both of us on the bike . Even if the fender makes contact with the tire I don't see where it could harm anything until I get it corrected by putting more tension on my shock springs . adjusting the dampener knobs or whatever . Like I said, the worse case scenario I will install the rubber bump stops temporarily to limit the shock travel . I don't think with me alone on the bike there will be any problems at all with the 2" fender to tire clearance .

Jack

[hogv8]

I sure would like to hear from some of you European guys that run your fenders so close to you tires and what you have found .

Jack

[SRF]

Rob, in order for tightening the springs to make the shocks longer it would have to mean the shocks were not already fully extended with the current preload. So if in fact less preload means the weight of the bike would compress the shocks slightly, but at that same time you could lift the frame of the bike by hand and fully extend the shocks, with the spring still filling the available space. Then increasing preload of the spring to make the shocks fully extended and hold the weight of the bike higher must make them stronger/stiffer. Below and up to spring adjustment to the point of full shock extension I agree stiffness would not be effected but if the springs are adjusted beyond that point they will be compressed to a tighter which will support more wieght. I believe there are different adjustment ranges that prove both theories right and wrong.

Shane

[hogv8]

I talked to Andy on his fender height on his Stingray bike and he said he said he has 1 1/2" fender to tire clearance and his fender never hits the tire but if you look close he has his shock springs cranked up quite far and it probably rides pretty hard . Of course this would vary as to what lb. springs are used .

Jack

[AR]

I talked to Andy on his fender height on his Stingray bike and he said he said he has 1 1/2" fender to tire clearance and his fender never hits the tire but if you look close he has his shock springs cranked up quite far and it probably rides pretty hard . Of course this would vary as to what lb. springs are used .

Jack

Jack you might recall the first thing Olaf did with his spanking new SS was change the shocks to a longer unit available from Aldan...he reckons clearance in corners was hopeless. If Andy still has the stock shocks then I believe he is winding them up to obtain more height/clearance and using my theory the ride would be the same...adjusting the damper control would stiffen the ride as far as the shock component can do. I didnt quite understand what Shane was saying above but at the moment it still looks like we have a heavily weighted against me hung jury....

[SRF]

Here is my explanation in different words and I am describing traditional spring where is a variable rate spring could cause even more things to consider. If you have the spring off of the shock and fully extended on the floor, depending on it's capacity you can probably manually compress it slightly but not all the way. As you bent the spring coil it takes more force to continue as the spring is pushing against you. If the spring is mounted back on the shock and preloaded beyond the point needed to support the weight, this extra preload is available to support even more weight before compressing more due to the fact it is already compressed beyond the point needed for the weight on it.

Shane

[zenbiker]

Rob
Once the shocks are fully extended, winding up the springs DOES preload the shocks. The shocks can only extend to their limit and further winding of the springs simply has to preload-load them.
The reason heavier springs are used is that even though weaker springs may be preloaded-loaded to the same total pressure as heavier ones, their resistance per inch of travel remains the rate it was before preload.
Heavier springs are rated in lbs./inch of travel regardless of the preload-load. Get my point?
Weaker springs = 200 lbs/inch of compression
Heavier shocks = 300 lbs/inch of compression
This remains true at any shock length. For example, a 200 lb. spring will only give 200 lbs of resistance per inch of travel even if is already half compressed or if it is not compressed at all! The same is true for any spring rating.
Is this clear?....Joe

[AR]

Tin hats on....Aussie is in the house.

[AR]

Rob
Once the shocks are fully extended, winding up the springs DOES preload the shocks. The shocks can only extend to their limit and further winding of the springs simply has to preload-load them.
The reason heavier springs are used is that even though weaker shocks may be preloaded-loaded to the same total pressure as heavier ones, their resistance per inch of travel remains the rate it was before preload.
Heavier shocks are rated in lbs./inch of travel regardless of the preload-load. Get my point?
Is this clear?....Joe

....the thing is, if you read your manual you will find that the factory shocks are set at the 50/50 mark for extension/compression...according to Aldans cattledog http://www.aldaneagle.com/AldanCatalog. ... wnload+Now you got about 3.7 inch of overall travel which means you got to wind up your shock up near 2 inches before you start compressing the spring. I dont think we are talking about getting pre load by winding 2 inches here...I would obviously agree with that, it is the concept of getting preload prior to reaching full extension of the shock I am arguing about. You will also note in their brochure that they DO NOT recommend running the shocks without extension available because DAMAGE FROM EXCESSIVE REBOUND FORCE will occur. Therefore, if we wind our springs up 2.5 inches we are doing what ALdan dont want us to do....tell me that I'm still wrong?

[zenbiker]

Shit, Rob...I've preloaded my shocks from day one. Now you are talking warranties not actuality. Such BS! :
1. You can preload the shocks by turning the springs up against a fully extended shock.
2. Thicker springs make for more resistance per inch of travel than thinner springs torqued up to more pressure. This is true at EVERY AND ANY SPRING LENGTH
3. Bullshit about needing "breathing room" for the springs! Crank em' up to where you want them.
4. I can't tell you what a difference I felt putting 350 lb/inch springs on my Boss.
The bike rides "flatter" and much better now!
Joe

[AR]

Shit, Rob...I've preloaded my shocks from day one. Now you are talking warranties not actuality. Such BS! :
1. You can preload the shocks by turning the springs up against a fully extended shock.
2. Thicker springs make for more resistance per inch of travel than thinner springs torqued up to more pressure. This is true at EVERY AND ANY SPRING LENGTH
3. Bullshit about needing "breathing room" for the springs! Crank em' up to where you want them.
4. I can't tell you what a difference I felt putting 350 lb/inch springs on my Boss.
The bike rides "flatter" and much better now!
Joe

Thanks Joe for entertaining me with this as by now most people get bored with me and go watch the grass grow. So let me get one more contribution from you and respond again with;

Bingo on number 1!
Couldnt agree more with 2.
Its Aldan that says dont do it on 3 and its not really what this is all about.
4 is good all round for that slammed look, performance, and short ass's, & once again not really what I'm on about.

With ALL the above we are saying the same thing so lets put all of that aside.

So, and here we are at the crux of my torment.....what happens when you wind the spring up on a Boss Hoss shock that is not fully extended? AND I promise what ever you write next will be the last word on the subject cause Jack is pissed at me for highjacking his thread and I'm sure everyone other than Shane couldnt give a rats.

Aussie.

If you want me for anything I'll be with Carby in 'deep thoughts' watching 4 hour docco's.

[zenbiker]

Rob...my boy. If you wind the spring up with a non-fully extended shock, the spring will keep extending the shock until the shock is fully extended. If you stop short of full extension, the spring will just act as it's inherent qualities dictate. I'm not sure what you are missing here, Robbie...Joe

[AR]

Rob...my boy. If you wind the spring up with a non-fully extended shock, the spring will keep extending the shock until the shock is fully extended. If you stop short of full extension, the spring will just act as it's inherent qualities dictate. I'm not sure what you are missing here, Robbie...Joe

TA DA

I just wanted to hear you say it dad

I know, I lied....I'm still talking about it and sorry again Jack but it is related to your fender mounting thoughts. I hope others can interpret the meaning behind your above statement Joe.

Case closed.

[hogv8]

No problem Rob but you must understand what Joe and I are both saying . IF THE SHOCK IS FULLY EXTENDED BY THE SPRING PRESSURE WITH NO WEIGHT ON THE BIKE TO BEGIN WITH , NO MATTER HOW MUCH YOU CRANK THE SPRING UP IT WILL NOT RAISE THE FRAME ANY HIGHER . THE SPRING WILL NOT COMPRESS AS MUCH WITH WEIGHT ON THE BIKE , THE RIDE WILL BE STIFFER THUS LESS CHANCE FOR THE FENDER TO HIT THE TIRE BUT THAT'S IT .

Jack