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Old 03-18-2012, 03:45 PM   #16
PSchrauber
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Anyway when you are around on a new bike or a new bikesport everything is new and there is this request inside telling you are you now doing the right thing or is this nuts again ...

If you are in weight above or less then Joe Average the above question may circeling around your brain depending the suspension, befor this will couse trouble while circeling with the bike around any trees, there is a neat little decription about adjusting your suspension fork and expecially shocks from Öhlins, you find it here: http://www.zupin.de/uploads/tx_userz...7252-01_01.pdf

The site where you can upload the file is in Germany, (German Importer Zupin for Öhlins shocks and forks), but the document is written in English and explains and give the adjustments for setting up of sag, compression and rebound, (no doctoral thesis just eight pages).
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Old 03-19-2012, 01:05 PM   #17
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Throttle Jock...

I hate putting this information up here, that I was almost 280 lbs (nekid). I guess I should be proud of losing some of it... Maybe you can figure out what you need to do?

If someone owned your bike, and when tying the bike into trailer or truck, without MERCY pully straps tight, you will find that the springs will collapse (relatively) over time. when I load bikes, I losen the straps whenever Im not traveling (as in the night before I leave) etc.

Plus I have straps and things with redundancy and placement of hook ends, so I never just sinch the hell out of the straps! this means the bike is never sucked down full suspension travel, to haul it... be it front or rear on pickup bed or 3 row trailers... there are better ways, like redundancy for strap failures IMHO.

Anyway, assuming there is nothing "broken" on front forks, on your bike...

whenever I got a bike, 08 raga 300 (previous bike) for example...

I would I put 2 10% stiffer springs, into it and the (hope memory is correct) it was either 15% or 20% stiffer rear spring, and on of the last things I had done with that setup, I had the Sachs shock rebuilt, valved differently. I loved it, though front forks were borderline stiff, anyone under 220 hated them.

Then I lost 60+ pounds. IT didnt come off overnight though... so about 2/3 of the way, we had a muddy trials, which I had ONE HELLVUA time in, at least I felt I worked too much harder than I should have had to, for traction. Just about that next weekend, I swapped bikes (to the 2010 Raga 300) only installed 1 front spring. cranked a few round into rear STOCK spring. it has been riden this way every since, and I like it MUCH better.

I now weigh like 210 ish (nekid). so compared to most expert/masters Im still a fatass. I have left in 1 stiff front spring, sold the other to fellow rider (you have to buy in pairs)... I removed everthing not stock, from the 08 raga, as my kid rides my old bike, he's 5-11 and under 200, he thought 190 at most? I didnt double check his weight. But it just seems fine, he's amature, and if he would work at it, intermediate rider.

I still dont like big drops. but nothing BANGS on our bikes... that banging scared me when you posted originally! But as I thought about it, I thought someone without too much experience with trials bikes, might jump something a MX bike could handle, and make things bang easy enough. I mean a buddy of mine (years ago) bought a montessa trials bike, but when to flat track it for an hour with some people he met at the riding are, burnt it up that fast.

hopefully everyone noticed I stated that messing with the suspension (unless there is a problem) was silly for almost any beginner to NOVICE winner rider. as we're assuming you bought a bike that new that works good? and that we know that there is too many other things to learn. But if your big and the previous owner was small, or vice versa, you need help getting the suspension at least to where it can be adjusted closer to your weight, which is mostly done with the 2 things I pointed out, that spacer in the front (you should keep the stock one) make new ones out of PVC, that either add lenght (preload) or shorter for lighter people. lighter people have less problem adjusting these bikes IMHO, but I'm definitely not one of them, so Im guessing by adjusting my son's bike since he was 12 and riding a 125. and rear springs have lost of preload adjustment.

By all means you should get experienced friends and trials buddy's to "try your bike" or at least look and listen to yours, This way, if something is messed up, you catch it instead of assuming it is normal...

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Old 03-20-2012, 12:11 AM   #18
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An awful lot of people lash their bikes down with suspension compressed, and as you rightly say this does very much reduce the life of the springs. Its a very good idea to either work out a way of transporting bikes without compressing suspension, or to change fork springs once a year so no problems with weak springs.
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Old 03-20-2012, 03:19 AM   #19
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Wow what a blast and what a big help my first trials event was! There were luckily two extremely helpful guys on the same bike there to help out. The issue I was feeling is that the previous owner had installed a 3" stack PVC spacer presumably to stiffen the fork. The result was only that I've lost all but 2.5" of fork travel, it bottoms against compressed spring and spacer about 4 inches too early. Comparing side by side with another raga was confirmation (and dumb luck that one happened to be there and in my same class). At any rate I'll be ordering a set of 10 percenter springs from lewisportusa and rebuilding before my next event.

Btw, I'm hooked. Big time. I started in novice this time at everyone's advice but then moved up to intermediate after 2 sections. That was a great, helpful group. Ended up winning the class with 13 points (5 of which were very dumb, I didn't know u couldn't roll backwards to set up for an obstacle), and will move to sportsman for the next round. I'm excited to Keep learning and meeting such a neat group of guys who share the passion of going slow! Thanks again for the tips, all
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Old 03-20-2012, 06:19 AM   #20
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Quote:
Originally Posted by ThrottleJock View Post
Wow what a blast and what a big help my first trials event was! There were luckily two extremely helpful guys on the same bike there to help out. The issue I was feeling is that the previous owner had installed a 3" stack PVC spacer presumably to stiffen the fork. The result was only that I've lost all but 2.5" of fork travel, it bottoms against compressed spring and spacer about 4 inches too early. Comparing side by side with another raga was confirmation (and dumb luck that one happened to be there and in my same class). At any rate I'll be ordering a set of 10 percenter springs from lewisportusa and rebuilding before my next event.

Btw, I'm hooked. Big time. I started in novice this time at everyone's advice but then moved up to intermediate after 2 sections. That was a great, helpful group. Ended up winning the class with 13 points (5 of which were very dumb, I didn't know u couldn't roll backwards to set up for an obstacle), and will move to sportsman for the next round. I'm excited to Keep learning and meeting such a neat group of guys who share the passion of going slow! Thanks again for the tips, all
Glad to hear that you sorted out the clank. I was curious about that.

Sounds like you're well on your way to being a great rider!
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Old 03-20-2012, 07:01 AM   #21
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Congratulations Throttlejock. You have found the best resource there is for Trials information, the experienced riders at your local Trials events.
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Old 03-20-2012, 11:21 AM   #22
mung
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Trials suspension

Best place for fork springs--Marzochi[?] springs are the same as Zoke downhill bicycle fork springs.Stock Raga springs are .30.Bicycle fork springs are available in.20,.30 and.40.I put the .40 in with half the stock preload and they work very nice for my 230 pounds.They only cost 40 bucks for a set at a bicycle shop and they are the same spring. I use 10 wt. oil in compression side and 5wt. in rebound side both at 100 mm from top of tube.My Raga came with an Ohlins[the good one] and springs are available at Ohlins USA for any weight you want for about 42 bucks shipped.Preload--Preloading a spring does not make a spring stiffer.It just makes the initial movement of fork rougher with no gain in overall stiffness.If you want to make a fork work right the spring weight needs to match the persons weight.Good quality springs should not be bothered by being held in tension.Do you release the tension on the valve springs in your truck each night? Do they seem to work ok the next day? Above all,enjoy your riding. Mark
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Old 03-20-2012, 06:58 PM   #23
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Best place for fork springs--Marzochi[?] springs are the same as Zoke downhill bicycle fork springs.Stock Raga springs are .30.Bicycle fork springs are available in.20,.30 and.40.I put the .40 in with half the stock preload and they work very nice for my 230 pounds.They only cost 40 bucks for a set at a bicycle shop and they are the same spring. I use 10 wt. oil in compression side and 5wt. in rebound side both at 100 mm from top of tube.My Raga came with an Ohlins[the good one] and springs are available at Ohlins USA for any weight you want for about 42 bucks shipped.Preload--Preloading a spring does not make a spring stiffer.It just makes the initial movement of fork rougher with no gain in overall stiffness.If you want to make a fork work right the spring weight needs to match the persons weight.Good quality springs should not be bothered by being held in tension.Do you release the tension on the valve springs in your truck each night? Do they seem to work ok the next day? Above all,enjoy your riding. Mark
Ahhh now you tell me! I ordered a set of +10% springs from lewisportusa today fit 3 times that$. No matter, I'm excited to ride this bike with working suspension
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Old 03-21-2012, 06:51 AM   #24
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Best place for fork springs--Marzochi[?] springs are the same as Zoke downhill bicycle fork springs.Stock Raga springs are .30.Bicycle fork springs are available in.20,.30 and.40.I put the .40 in with half the stock preload and they work very nice for my 230 pounds.They only cost 40 bucks for a set at a bicycle shop and they are the same spring. I use 10 wt. oil in compression side and 5wt. in rebound side both at 100 mm from top of tube.My Raga came with an Ohlins[the good one] and springs are available at Ohlins USA for any weight you want for about 42 bucks shipped.Preload--Preloading a spring does not make a spring stiffer.It just makes the initial movement of fork rougher with no gain in overall stiffness.If you want to make a fork work right the spring weight needs to match the persons weight.Good quality springs should not be bothered by being held in tension.Do you release the tension on the valve springs in your truck each night? Do they seem to work ok the next day? Above all,enjoy your riding. Mark
Well, in "practice" pre loading the spring does make the spring stiffer, for the bike and rider, because even if you map it with a chart, you can measure the difference in the forces it takes to 'move'...

if no preload leaves you with it taking 40lbs force, to begin movement, for the 1st bit of travel, say 1/2 inch for easy calculations, from there the design of the spring dictates what the exponential rate would be. The gasgas in question, has almost 7 inches of travel gives us 14 points to check the amount of pressure it takes to compress further, using half inch measurements. So, preloading 1/2 is like moving up the chart, it now takes x amount force more at start and the new highest values have moved up a notch, just closer to maximum compression design of the spring, which would be measured just before coil bind. Yeah 10% stiffer design springs, this whole travel would have modified exponentially the rate at which we have to apply weight to move the spring to compress it another inch. So technically, preloading... no it did NOT affect the exponential "rate" of the spring, but it affected the where/range of effective rates we are "using'.

Lets look at it more, with some fake easy values becuase I'm not an engineer, and dont have real values that would be hard to follow anyhow.

Lets take the stock spring, and say at rest with stock "preload" in one shock assembly and not counting resistance due to seal and or fluids... this is a paper engineering study... By a person that doesn't like math anyhow...

So lets just say and agree for this study, that the stock spring, takes oh about 40 lbs of force to move spring from Static or at rest, to 1/2 inch comression, then next 1/2 inch takes 42lbs, the next takes 45, which creates sort of a bell curve when plotted, that curve is the "exponetial rate" of the spring... So Im not doing a bunch of math, Im painting a picture, so plot in out in your head, and so on for 14 different one half inches. plus we dont ever use that last 2, 1/2 inch measurements designed in the spring (if we dont add too many spacers that is, due to lenght of fork tubes, and what gasgas says about addng preload to the spacers...

ok? so far?

So now I add the 1/2 inch preloaders via adding to the spacer:
I have now made that 1st 1/2 inch move up the graph, and increased how much it takes to now move the spring from static 40 lbs, to the new 42lbs of force of previously plotted 2nd 1/2 inch, everything now overlays up one plotted value or x is now +1. If I add one inch preload, x moves up now 2 spots on the chart.

OK?

SO knowing that the 10% stiffer srpings, have a different expontail rate, BUT it is already given, we can take this fake study and draw a conclusion:

If I take the 10% stiffer spring, you just add 10% to the exponental rates of the spring, so instead of "stock" preload lenghts, being 40 lbs, it is now starting with 10% more or 44 lbs, the next step takes it up faster on forces, so that point #2 went up 10%, so the second 1/2 inch is now 46.4 lbs of forces needed, plot that on the new bell curve, up through almost coil bind, and or until forks cannot move farther, you know up to our 14th 1/2 inch.

AND,

if I preload that 10% stiffer spring, you can see it really takes a lot of forces to compress the spring up to the 14th half inch...

I picked 40 as a guestimate, since we have 2 springs in front, and I can (without even doing math) imagine that 1st values actually is somehwere near 40lbs, since the bikes weigh in at <140 lbs total, maybe 60% of weight is on front, equals 84 lbs? well hell Im not all wet?

Anyhow, I think if you weigh 200 lbs fully dressed, the pair of 10% stiffer springs, you will HATE them, because with both of them in use, you effectively took even my dumb little study, and doubled it, because you have 2 springs @10% = 20%... Just sayin... FROM MY EXPERIENCE, and I'm anywhere from 10 to 20 lbs heavier ready to ride than you are, 2 10% springs were too much when I was 40 lbs heavier than you.

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Old 03-21-2012, 08:43 AM   #25
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More suspension

I am about 250 ready to ride.With the heavier springs the bike sits higher in the suspension stroke and is at the same time plusher on the little bumps and stiffer on the big bumps.With more preload you would gain on the big bumps but lose plushness on the little stuff. I think that is the advantage of having the correct springs for the riders weight-you have good suspension on both ends of the spectrum.Of course any decent rider is going to kick my fanny no matter how good my suspension is set up.
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Old 03-21-2012, 09:04 AM   #26
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I am about 250 ready to ride.With the heavier springs the bike sits higher in the suspension stroke and is at the same time plusher on the little bumps and stiffer on the big bumps.With more preload you would gain on the big bumps but lose plushness on the little stuff. I think that is the advantage of having the correct springs for the riders weight-you have good suspension on both ends of the spectrum.Of course any decent rider is going to kick my fanny no matter how good my suspension is set up.
Yep, I like softer setup now, and it was MY OPINION, just sayin...

when I went below 250 I guess, the bike, especially front tire would "slip" off muddy slippery rocks, or even just stop or attempt to stop me, in dry conditions... This was proven even more to me to be easier at last club event, at damn near same wet conditions, on my bike with softer spring setup... (it is all about how it feels to you, to me yeah, probably more than just slightly you know, it is how it feels and again it is IMHO)...

Oh and I always used stiffer setup in my forks, just because I HATED even the notion, that front might (all from past expeiences on many bikes) buckle under on a drop, or worse catch skid plate when nobody else was, you know that "Suprise" knock you off balance thing that can really hurt your confidence, lol.

What I have learned, and seen, that I've apprently always did anyhow, was "help" by unloading suspension whenever I got in situations, so the only thing left was, when you jump up a ledge, for example, but landing area has bumps or garbage, the front tire tended to stop instead of compress and rol over...

again Im trying to type out about a feeling of a "tendancy" that became apparent to me... now I know, usually I could if had balance and poise to overcome, just unload pressure on bars or whatever, but when wet, why work that much harder, why having to balance harder, and have to make up for too stiff front end...?

that was my deciding factor anywho... Your milage WILL vary...

Please keep in mind, Im not tryin to make "wholesale changes" to how you like it. Im talking about that "tiny bit" that tendancy, the reason bikes didnt get to 145lbs or less, overnight since 1975... those little gains, that feel better or what not.

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Old 03-21-2012, 11:19 AM   #27
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I am about 250 ready to ride.With the heavier springs the bike sits higher in the suspension stroke and is at the same time plusher on the little bumps and stiffer on the big bumps.With more preload you would gain on the big bumps but lose plushness on the little stuff. I think that is the advantage of having the correct springs for the riders weight-you have good suspension on both ends of the spectrum.Of course any decent rider is going to kick my fanny no matter how good my suspension is set up.
That generally parallels my experience when I move to a stiff-than-oem (and correct-for-my-weight) spring rate too. I'd guess that bikes are targeted at a 150-160lbs rider or thereabouts. I'm 191 w/out gear, probably 205 in boots & a helmet. I have my roadrace bikes set up for 205lbs and they're just about perfect. Anyway, I digress - the thing is, with too-soft stock springs the only thing a fatso like me is to do to try to get in the ballpark of the correct sag is to crank down the preload. Even so, I'm .75-1" deeper in sag than I should be (on this bike in particular), and even if the forks didn't have the bunghoolio-installed spacers which limit travel, I'd be deep into the mid-stroke of the travel when just riding around.. into a harsher range of suspension than I should ideally be, commensurate with the speed I'd be traveling. With a stiffer spring it'll bring me back into the right range, and with oil weight changed to match all of a sudden the suspension will begin to operate like it's supposed to, like it would for that 150-160lbs target rider. In theory.

Having said all that though, I'll be satisfied just to have full travel back and to stop hearing (and feeling) those scary clunks. My wrists will thank me.
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Old 03-21-2012, 12:59 PM   #28
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More suspension

When you do your spring change I assume you will change the oil? For the clunk I would check that the cartridge rod nut is [was] tight to forkcap and that bolt in bottom of fork is tight.That and a good bleed of the cartridge with new oil and springs should do wonders for the front end. Also my bike [04 300 Raga] was targeted to a gentleman named Adam Raga.I stood next to him at the world round at Donner, California in 1997 and if he weighs 135 pounds that must be with a big dinner and a backpack on.He is a very tiny guy.He came to the middle of my chest.

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Old 03-22-2012, 07:56 AM   #29
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That generally parallels my experience when I move to a stiff-than-oem (and correct-for-my-weight) spring rate too. I'd guess that bikes are targeted at a 150-160lbs rider or thereabouts. I'm 191 w/out gear, probably 205 in boots & a helmet. I have my roadrace bikes set up for 205lbs and they're just about perfect. Anyway, I digress - the thing is, with too-soft stock springs the only thing a fatso like me is to do to try to get in the ballpark of the correct sag is to crank down the preload. Even so, I'm .75-1" deeper in sag than I should be (on this bike in particular), and even if the forks didn't have the bunghoolio-installed spacers which limit travel, I'd be deep into the mid-stroke of the travel when just riding around.. into a harsher range of suspension than I should ideally be, commensurate with the speed I'd be traveling. With a stiffer spring it'll bring me back into the right range, and with oil weight changed to match all of a sudden the suspension will begin to operate like it's supposed to, like it would for that 150-160lbs target rider. In theory.

Having said all that though, I'll be satisfied just to have full travel back and to stop hearing (and feeling) those scary clunks. My wrists will thank me.
Yep, you will have it sorted I think, my "un needed" worry, why did I worry about someone I dont even know's trouble? Because I am the TRIALS EVANGELIST, lol. My point, and if I knew you better I think I could have risked being lots more "direct" than hoping you might somehow magicaly figure out what I was warning about, with the big old posts...

Im worried that the springs you have are nackered... way soft due to sinching bikes in trailers and what not... then if you replaced with FRESH NEW "stock" springs, it might fit you better, with even adjusting up to maybe 1/2 inches of spacer added to one or both sides, measured from STOCK spacer size, of which we'd have to look up, or take my bike apart to recall the actual lenght.

My worry is, from my experience, 2x 10% stiffer than stock springs, for a person who weighs 190 LBS, seems to me going to be an ERROR... ONLY because when I, who was at one time 280 hated 2x10% stiffer than stock springs & stock spacers.... you get me?
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Old 03-22-2012, 09:41 AM   #30
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Yep, you will have it sorted I think, my "un needed" worry, why did I worry about someone I dont even know's trouble? Because I am the TRIALS EVANGELIST, lol. My point, and if I knew you better I think I could have risked being lots more "direct" than hoping you might somehow magicaly figure out what I was warning about, with the big old posts...

Im worried that the springs you have are nackered... way soft due to sinching bikes in trailers and what not... then if you replaced with FRESH NEW "stock" springs, it might fit you better, with even adjusting up to maybe 1/2 inches of spacer added to one or both sides, measured from STOCK spacer size, of which we'd have to look up, or take my bike apart to recall the actual lenght.

My worry is, from my experience, 2x 10% stiffer than stock springs, for a person who weighs 190 LBS, seems to me going to be an ERROR... ONLY because when I, who was at one time 280 hated 2x10% stiffer than stock springs & stock spacers.... you get me?
Totally, and I appreciate the concern! :) I was thinking that if it turns out that the +10 springs are too much, I can just drop one of the stock springs w/ correct preload spacer back into one of the legs. It'll be good for me to get to know the suspension on this bike a little more anyway so taking it apart a couple of times won't be so bad if that's what it comes down to. Thanks again man, I'll keep you all posted on the results!
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