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Which Stiffer Springs?


spark
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Heya I'm hopefully going to be getting a new TXT 300 soon. I'm sure I will be too heavy for the standard springs as I weigh 90kg to 98kg (without gear) depending on the season and how much junk food I've been eating :thumbup:. Lewisport do a 10% and 20% stiffer than stock set of fork and shock springs. I'm thinking the 20% stiffer springs would be the right ones, whats your thoughts? (on the springs not my diet!)

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If you like to do alot of big hits, and like to hop, the stiffer springs will be better, but there is a trade off with feel and compliance over the small stuff. If you ride alot of slippery, muddy events, maybe error on the soft side is a better tradeoff.

I went with 20% in the rear and ended up with only 1 20% spring in the front (net 10%) - the forks (Zokes) were already pretty stiff and I wasnt bottoming them hard like the rear. It took some getting used to, and some setup changes, but I really like it. The bike rides alot more lively and the energy I put in, I can get back. (I just really overwhelmed the stock springs - the sag was way off (I was panning out on alot of stuff) and the bike geometry suffered)

I think the avg 180 to 200lb rider would be well suited with the 10% stiffer rear spring only. Your right in the "could go either way" zone, so it will really depend on your riding preference. I think anyone over 230 to 240lbs with gear on will want the 20% rear for sure. Dont forget you can mix and match the fork springs to get a combined spring rate.

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Most of the European Trials bikes (well that is all of them d'oh)are set up for a 70kg rider. Fork and shock spring adjustment can take that up to 85kg (ish).

I'd agree with the other post. I would also suggest that a bikes suspension will work better for a rider if there is NO pre-load on the springs.

If you are a faster aggressive rider choose the heavier spring. What do the Lewisport team suggest?

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If you like to do alot of big hits, and like to hop, the stiffer springs will be better, but there is a trade off with feel and compliance over the small stuff. If you ride alot of slippery, muddy events, maybe error on the soft side is a better tradeoff.

I went with 20% in the rear and ended up with only 1 20% spring in the front (net 10%) - the forks (Zokes) were already pretty stiff and I wasnt bottoming them hard like the rear. It took some getting used to, and some setup changes, but I really like it. The bike rides alot more lively and the energy I put in, I can get back. (I just really overwhelmed the stock springs - the sag was way off (I was panning out on alot of stuff) and the bike geometry suffered)

I think the avg 180 to 200lb rider would be well suited with the 10% stiffer rear spring only. Your right in the "could go either way" zone, so it will really depend on your riding preference. I think anyone over 230 to 240lbs with gear on will want the 20% rear for sure. Dont forget you can mix and match the fork springs to get a combined spring rate.

I see what youre saying about me being in the either way zone, thats why I asked because I too feel I could go either way. My 2001 Sherco 2.9 is WAY under sprung for me, it bottoms out on everything. I like the way you talk about getting the energy you put in back, at the moment with my Sherco I feel like I am getting no energy back and it is difficult to hop. Of course it is an old bike and the Gas Gas is sure to be miles better but I definately like the thought of the bike becoming more lively with a stiffer spring.

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Most of the European Trials bikes (well that is all of them d'oh)are set up for a 70kg rider. Fork and shock spring adjustment can take that up to 85kg (ish).

I'd agree with the other post. I would also suggest that a bikes suspension will work better for a rider if there is NO pre-load on the springs.

If you are a faster aggressive rider choose the heavier spring. What do the Lewisport team suggest?

To be honest I never asked them, perhaps I should.

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No pre load on the spring? With a bike like the Sherco rear shock do that mean it should be set so that at rest there is almost a bit of slack in the rear suspension before it is loaded?

I must confess to having my rear suspension pre loaded with almost no damping and it was described by an expert rider who borrowed it for the day as having dead rear suspension.

It is the standard 08 Olle adjustable with a standard spring.

It seems to be said that if the Shercos have an Achilles heel it is in the rear suspension set up or damping.

Any comments would be appreciated perhaps I have just made things worse.

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I do think that Sherco rear suspension is basic (I haven't ridden the newest models though),good grip but a tad wooden (too much damping?) which gives me sore knees.

Does anyone know where to get an uprated spring as I weigh in at 95kg?...97 with a h4rd-on :thumbup: .

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Most of the European Trials bikes (well that is all of them d'oh)are set up for a 70kg rider. Fork and shock spring adjustment can take that up to 85kg (ish).

I'd agree with the other post. I would also suggest that a bikes suspension will work better for a rider if there is NO pre-load on the springs.

If you are a faster aggressive rider choose the heavier spring. What do the Lewisport team suggest?

I got a reply from Mandy at Lewisport and she said that 10% stiffer springs for forks and shock would be more than adequate for my 98kg (216lb) mass. Also I should not be mixing different rates like 20% for the shock and 10% for the forks. They obviously know their stuff, but it just doesnt seem to add up (if the standard suspension is setup for a 70kg rider). I think the right way to work out the load on the springs is to add the mass of the rider to the sprung mass of the motorcycle. So 68kg - wheels, swingarm, calipers, bottom of forks etc = 48kg (as an estimate, havent measured!). So the load on the standard spring with an ideal 70kg rider should be roughly 118kg. With me on the bike it would equal roughly 146kg. That is a 24% greater load on the springs, so how could a 10% stiffer spring get me sprung equal to a 70kg rider?

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In terms of mixing and matching, my experience has been a good one. I cant think of any mechanical reason why this is a problem. I have had conversations with Adrian about my setup with stiffer springs and the only thing he mentioned to me was that he wanted to keep the spring install identical to stock (keep the preload spacers ect..) so that there was no (less) confusion on how they were assembled. (Note - My HD fork springs were from the old supplier and dont use the preload spacers)

Also - dont forget that it takes several hours to break in the Marzocchi's - they can be pretty stiff for the 1st 10 hours or so. I put the stiffer spring in the rebound side and ended up using the stock weight oil and level. (I assumed incorectly I would need more rebound damping, but changed back to the 7.5 wt and like it) I added about a 1/3 turn more damping to the rear. I was suprised how little adjustment the Sacks shock needed to make a noticable difference.

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Been there! ----done that !! -=----trust me-- use the 10%-- ther is WAAAAAAAY to much info going on here-- its a trials bike not the space shuttle!!

Silly me, and here I thought information was what the OP wanted....I guess I should just stick with analogys instead.

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In terms of mixing and matching, my experience has been a good one. I cant think of any mechanical reason why this is a problem. I have had conversations with Adrian about my setup with stiffer springs and the only thing he mentioned to me was that he wanted to keep the spring install identical to stock (keep the preload spacers ect..) so that there was no (less) confusion on how they were assembled. (Note - My HD fork springs were from the old supplier and dont use the preload spacers)

Also - dont forget that it takes several hours to break in the Marzocchi's - they can be pretty stiff for the 1st 10 hours or so. I put the stiffer spring in the rebound side and ended up using the stock weight oil and level. (I assumed incorectly I would need more rebound damping, but changed back to the 7.5 wt and like it) I added about a 1/3 turn more damping to the rear. I was suprised how little adjustment the Sacks shock needed to make a noticable difference.

Hi laser1, thanks I have enjoyed your posts. It's good to know the steps you have taken and the results achieved.

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Been there! ----done that !! -=----trust me-- use the 10%-- ther is WAAAAAAAY to much info going on here-- its a trials bike not the space shuttle!!

Hi Adrian, you must have the most experience with these springs so I will take your advice and go with the 10%. Thanks.

Edited by Spark
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Sorry Laser1-- wasnt meaning to be clever-- its just we see this day in day out, i have been doing this both here in the USA and in UK for the last 32 years -- i talk to lots of customers every day with questions on trials -- i also mechanic for gas gas at nationals and i have to say that in all honesty -- MOST riders will never know the difference-- when i say most i mean the majority-- not saying everyones this way , BUT-- the MAJORITY of riders are lower to middle class and in general they have soooo many other things going on that how the suspension is working is last thing on there mind-- many a time i have run a training class and found bikes completly blown and the riders dont even realise!---it seems everone wants to set there suspension to hop and nose wheelie before learning basics. Hopping and trick ridding will come automatically and trainning thereafter is much easier!-- it is very hard to try and teach someone to hop when they cant balace and do a full lock figure 8 turns!!!

The other thing you must appreciate is that every rider is not the same-- you and i may both be the same weight on the same bike in the same class and of eqaul level-- but you might be a heavy less technical rider than i -- vise versa-- so suspension on a trials bike is a very personal thing-- have it a soft as you can without bottomming out --obviusly drop off you would expect a bottom , but nothing very techcnical about drop off,s--the most important concepts of the trials motorcycle is based among other things about traction-- and for that we require a good soft slow suspension.

The Marzocchi suspension will take a little longer than 10 hours also-- probably more like 30-50 hours before optimum performance is achieved.

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