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Setting up a trials bike for a tall/heavy rider

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I've searched around and haven't found many specific answers for my questions so I want to start a thread to serve as a resource from this point forward.

First a little about me. I'm 6'6" tall, tip the scales at 240lbs and am new to trials bikes. My main purpose for a trials bike will be trail riding and eventually I might try my hand at a few trials.

On all my other bikes one of the first things I've alway had to do right off the bat is resping my bikes for my weight. From what I've seen most trials bike's stock setup is for a 80kg (176lbs) rider. Should I expect to need springs that are 35% stiffer than stock for the bike to ride correctly with a rider of my size? Sourcing the springs is easy and I the guy that has done my other bikes can get just about anything custom wound for about the same price as off the shelf springs.

Secondly ergos. I know I'm going to need to do something about the bar height. For pure trials riding I understand the reasons you might not want higher bars, but after riding a borrowed gas gas that had not been set up for a tall rider not only was it extreme uncomfortable, but it was quite difficult to see up the trail being so bent at the waist. Since I have a Montesa adding bar risers isn't an easy or cheap alternative because of the angled handlebar clamps.

What make a trials bend bar trials specific? From looking at bar specs it appears that most trials bars are relitively flat for their given rise with little pull back. Meaning the "up" bend makes up about 70-75% of the total rise of the bars leaving the ends close to level. On my other bikes I've found the Pro Taper Contour ATV High works quite well. It has 55mm of sweep and 121mm total rise, but only 70mm up bend so the other 50mm is made up in the angle of the grips. Would this be good or bad? I've also found the Pro Taper DRZ 110 ben bars are pretty close to the trials ratio 143mm total rise 123mm "up" bend and 44mm sweep. I'm leaning towards this bar since it's closer to a true 6" trials bar than Renthals 6" bar that no one in the USA seems to carry anymore.

Am I on the right track here? What else should I know?

Thanks.

Edited by brianjonesphoto

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The bend seems flat if you have the bars rolled too far back. When rolled a little forward, the tips of the bars are higher and fit the position of your palms better.

As your legs get more conditioned to becoming the primary suspension (The Rider's legs are 90 to 95% of the total suspension and the bike is designed that way), you'll tend to sink your knees a little as you tackle the rougher parts of the trails and then you can take a rest and lean on the bars a little.. And once you learn to take a softer grip with your hands almost open insted of clenched tight around the grips, that will give you a little more stand up room too..

For a tip on bar position and lever position for beginners, I made a video. Keep in mind that the bar position shown in the video is about as far rearward as you should ever use. As you get better and encounter tighter stuff, rolling a few more degrees forward works better. The steering geometery is set up for it. Here's the video. Use it as a starting point and adjust from there for your personal style.

Some people will whack you on the knuckles if you use more than one finger on the brake or clutch. I vary the number of fingers depending upong the situation and fatique and I have seen other instructors say one or two fingers as you wish also.

Edited by 2PLY

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Though this guy is showing the bar position for an Enduro Bike, he also is explaining the Trials Position... the only thing that is lacking in this video is a camera angle directly perpendicular to the bike to show the angles of the bars better.

While there at his You Tube Channel, watch some of the other videos because he understands how Trials techniques are valuable to Enduro and other riders. He has some good examples using Trials Riders on Enduro Bikes.. Check out his log jumping one.

Edited by 2PLY

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Hi, I'm 6' 3" weight 210. On my 4rt I used the V-mar top triple clamp with the optional 10 mm spacer to raise the bars. Another benefit is now you can run fat bars. Check the V-mar website for more info. I don't know what bend bar I was running. On the rear shock I used the TRP 10% stiffer shock spring. I did not change the fork springs. The Showa suspension on the Montesa is more capable of handling heavier riders than other brands. Going 30% stiffer on the spring rate would be way too much IMHO. Also, I ran the Jitsie footpeg mount brackets which moved the pegs back a bit which made for a better riding position. Have fun!

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Hey there. I'm in the same boat. Not tall, but 240lbs. I just brought this up with Adrian Lewis at Lewisport. He even saw me cruising the bike around. My feeling looking at video of myself is that too much travel is taken up with sag. Adrian said throw your conception of sag out the window though. His take is the bike should be as soft as possible without bottoming hard on pre-loading the suspension for an obstacle. He had springs, rather expensive springs, he could have sold me but told me to skip it and save my money. My take is that if you are new to trials you have so much basic learning to do that the suspension work will do little to fundamentally improve your riding. Instead work on that loose but active body position, hands, hips etc. Setting up the controls to suit you is another story. Adrian was cautioning against too high of bars unless dictated by back problems. The whole setup from his perspective was very different than a normal bike. Another example: lever angle. I run mine down quite a ways, in line with my arm etc. I've heard from a number of people, without good reason, that my levers are too low. I always kinda say thanks and leave them be, cause I know where my levers should be. Adrian explained that the downward levers invite your hand to slip forward off the bar in a hard landing, where flat levers will keep you arm/wrist behind your hand and not rolling forward causing broken wrists. Who would have known.

MP

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As always - The answer is: It depends and I agree that with a newbie rider, optimizing the bike suspension isnt a priority, but I can tell you from 1st hand experience that it makes a HUGE difference IF you want the MOST from your bike!

I find a well optimized bike makes me want to ride more cause its just works well and that translates directly to fun factor and capability. In my experience, 10% stiffer springs makes a big difference and is perfect for guys up to around 220 and a 20% spring will take you upto 260+. (Still on the soft side, but no longer a tail dragger) I would NOT go any higher than 20% if your under 260. (besides you will have to have them custom made if over 20%) I found that most people I asked had either never touched there suspension or were light enough to make do with the std suspensions. They all said - no need to change. But NONE of them had ever changed and optimized there suspension and never knew what they were missing IMO. Boy were they wrong. I did alot of experimenting and found +10% (1 20% spring) in the front and +20% in the back were perfect for me. I could now hit things hard w/o feeling like I just pounded a spike up my back. I could backoff the preload and the bike was now much more compliant and stable. The bike steered better, turned better and rode higher so I gained more peg and plate clearance. I remember thinking that I could now get the energy I load into the suspension BACK instead of just collapsing the bike. I had monkey motion for the 1st time! I encourage everyone to test stiffer springs out if they weight over 200lbs. The bike (GG's anyway) was designed for a guy who weight 65-75kg (143-165lbs. ) I think a 10% buffer on top of that doesnt hurt the performance much, but much more than that and you have now changed the entire bike geometry in a negative way. Of course, the only way to know for sure is to try it yourself. But I know I feel it was the best money ive ever spent on a upgrade and ive tried just about every upgrade on a GG. Most are bling, correct springs are vital IMO. Every rider (none were brand new riders) ive convinced to up-spring was happy they did. (probably only 4-5 guys though) I also ride alot of friends bikes and the new bikes seem to do fairly well until I start to push things and hit things hard. It's then I really notice a big difference. Could I live with it - yes, but wouldnt like it now that I know better.

Heres what Reiger suggest for springs on the 2011 Raga bike - lots of small increments in springs available. BTW - the stock spring is 67.5nm. I think the 2010 style linkage uses a 72.5 spring.

http://www.reigersuspension.com/index.php?page=main&id=1&nwsid=257

They also have shocks with H/L compression adj as well as hydro bump stop and rebound delay circuits. My guess is that they will show up on the 2012 raga - but can be ordered now.

Edited by laser17
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I bought an upgrade shock for my 07 Raga GG 300 a couple years ago and ordered the heavier spring with it at the time but do not know what the numbers are. I have not changed the front springs but just adjusted pre-load. Perhaps I would benefit from different front springs too.

But when it's all said and done, your bike should sink into at least 30% to as much as 40% of it's travel with just your weight on it. The Trials Suspension helps to keep the bike level and stable though small stuff while the rider is responsible for the big stuff. Also, in Trials, the suspension needs to drop as well as compress for obstacles to help keep the bike stable while preparing for the stuff your legs need to handle... Setting the sag too high (too stiff) will make it harder for the tires to follow the terrain in BOTH directions... up AND down without affecting the frame's stability and your handle bar action. It's something the fast riders don't really need to consider as much.

When adjusted correctly, you SHOULD be able to bottom the suspension while on flat ground by just jumping on the pegs as hard as you can. If it bottoms more easily than that, increase the pre-load on the spring. If you can't bottom it out, decrease the pre-load until you can just barely identify bottoming of the suspension.

With both hands on the tank and centered between front and rear wheels, push down hard and let it rebound. If both ends go up and down evenly together then you are set..

I'm shorter than you but I still weigh in at 240 with riding gear on. When I first started this sport, my bike weighed 236 and I weighed 175.. NOW, I weigh 240 and my bike is less than 150! That's how far the bikes have progressed!

Many variables and personal preferences to deal with. I must add that the advice Adrian Gave Mattpetty is sound advice too, especially for a beginning rider. As you gain experience, you'll know better what you want and you'll be more sensitive to the subtle changes that can make big differences in your ride and enjoyment.

I warn people away from tall bars, but I have to laugh when I remember my first year and saw a guy on a TL 125 Honda with VERY tall bars on top of RISERS.. I thought that was really cool and wanted to get the same setup but lucky for me, I got better before I could find the bars. this other rider had been riding longer than me so I thought he had the answer.. :lol: Now, he would die from embarrassment if I could produce a photo of his setup :bonk:

Edited by 2PLY

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Hey. Yeah I think you guys are spot-on. I'm sure that dialing in preload/springs would help any rider, but particularly more experienced riders.

On the other hand, I was SO happy not to be up-sold by Adrian on a bunch of parts and upgrades and that I didn't urgently need, and instead encouraged to continue improving my skills. I went back to the original post to see what type of bike BrianJonesPhoto was talking about and I get the impression that it hasn't been purchased yet. When I went to see Adrian at Lewisport I was ready to scrap my old 99 Gas Gas and blow a ton of dough on a new(er) bike, but I left really encouraged that my old bike was all I need at this point.

Laser described finally feeling like his bike was rebounding after he preloaded to jump something. I think you may have sold me! I can see where a bit heavier spring and less dampening would change my bike for the better and take some of the wallow out of it.

Have you already been riding Brian or are you about to get a bike?

MP

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Sorry I wasn't more clear in the first post. I'm a total noob but have had some time on Pro_Marinero's 321txt which he has dialed on for a rider our size. I've got 8-10 hours on it in the last month. I've also had a chance to ride a bike stock 280txt and I can tell what a difference taller bars and risers make. On the 280 I was barely able to see up the trail because of being so bent over.

I purchased a 05 4rt a couple weeks ago and an in the process of going through all the basic maintainance like I do with all the used bikes I buy. Since had the forms a part to change the oil and the rear suspension to lube the bearIng I took the spring s to my suspension guy to have them measured. If I decide to go with updated springs we can get me custom springs for what ever I need.

I think for a baseline I'm going to try to match the 321 as much as I can. I plan on going for a ride with on the montesa in its stock form once I get back together and see where I need to go. So far I have maybe 30 minutes of riding on it so I can't tell anything.

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On the 280 I was barely able to see up the trail because of being so bent over.

Trials helmets are cut higher in the front than other helmets, to allow you to lookup more easily.

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FWIW: Many guys online really seem to like the mod shock linkage for the Montesa. You might ask Chris Cullins about them as I have no direct experience with them. http://www.tec-cycles.com/id43.html (scroll down page)

Yeah I'm aware of the aftermarket link plate thanks. Infact the link plates where one of the parts on the bike there were worn beyond use (linkage bolts were loose and the holes had ovaliized). I decided to replace them with OEM so I can get a feel for the bike in it's stock form. I also have a hunch that the bigger riders use the aftermarket plates instead of using the correct spring rate.

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