Jump to content

brianjonesphoto

Setting Up A Trials Bike For A Tall/Heavy Rider

Recommended Posts

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" (2m) tall, tip the scales at 240lbs (108kg) 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 always 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.

Share this post


Link to post
Share on other sites
 

You are going to get many different opinions

To help with better ergo....

you should consider getting a different triple clamp and bar mounts from Vmar and adjustable bar clamps from S3

LewisportUSA

also lower foot pegs

I would say yes to heavier springs both front and rear, but keep in mind heavier springs will effect the shock rates and may need to adjust the valving

Also when you really start setting up the bike for just riding (non competition and usually stiffer) this will likely make the bike less competitive (typically we want softer to absorb impact and hold traction).....in other words it is very difficult to set up the bike to be really good at both

Share this post


Link to post
Share on other sites
 

I've considered the vmar top clamp but I want to hold off dumping too much money into the bike until I have more peg time on it. I'd rather spend $200 on new springs first.

Right now my goal is to get it set up and rideable then figure out what needs changing. Ican get the drz bars for less than $50 so it is my cheapes option and will get me in the neighborhood of where I think I want to be.

Share this post


Link to post
Share on other sites
 

The Renthals are really strong and hold up well. Bars can take a beating in trials so you may want to consider that in the cost equation. I think your smart to re-spring. The bike will handle like it was designed to. The proper spring and valving are often overlooked until you change them and realize the difference it makes. Many over preload the shock (instead of the proper spring) and it makes for a very harsh and unstable ride. One simple fix for the forks is to install HD springs (or spring) and add 10wt oil to the rebound side. (Im assuming the std setup is 7wt like on a gasser)

If your flush with money, the Raptor pegs are lower than others (lower profile as well) Stay away from the billet Al type as they tend to be tall. You can probably get different FP hangers as well.

also - dont forget to bend your knees and keep a wide stance.

Good luck

Share this post


Link to post
Share on other sites
 

What is the benefit of having lower foot pegs?

Lower center of gravity, lower polar moment of inertia etc etc?

Apologies, I'm a good engineer but a terrible trial rider!

Share this post


Link to post
Share on other sites
 

If you can engineer them use a pice of solid square section drop to make a drop link for you pegs? Fit the link into the existing holes and have a new hole lower down it to mount the pegs. This brings you closer to the top of the bike i.e the bars. Then fit risers the get the extra. You could also drop the forks through the yokes a bit but that may wreck ground clearance and make it very head shaky on the trail.

I think with your height it is going to be tricky to get the perfect ergos without spending big wonga. I'd sort the springs first and then go onwards from there.

Share this post


Link to post
Share on other sites
 

not wanting to confuse things but (should not admit to this) l am 275lbs and 6' 4" tall and ride a 03 290 sherco which is completely standard apart from tiping the bars forward to give me more room the suspension is as it came from the factory this l know as l have had the bike since new and it copes very well and when im on it can be very sucessful in the sections and is also happy blasting along between sections and on the trails. :thumbup:

Share this post


Link to post
Share on other sites
 

I think the nature of the sport demands soft supple suspension so extra weight is not all that bad. Once it's moving it can be useful momentum! Unlees your clanging by bottoming out repeatedly I would not worry. If you do springs need to be changed.

Share this post


Link to post
Share on other sites
 
 

Did you source your springs yet??

Yes there are 2ocal suspension shops that can custom wind anything I want as long as they have the required measurements.

Share this post


Link to post
Share on other sites
 
 

I'm 6'6" and 95kg..... I put in 2" bar spacers and new bars with a 4" rise rather than the standard 2 and a half ( I think) which ossa comes with. Instant cure to sore neck, looking at the front wheel too much and now much better centred on the bike. Tipping the bars forward can give you a bit of wrist strain and unless you are an excellent rider it seems to put you too far forward and your front wheel tucks in and pushes on some tighter turns.

Wide stance and slightly bent knees really helps as does slightly arching your back.... think of the cobra position in yoga! I find that I can now really use the bike and the suspension standard set up really works for me.

I wouldn't drop the pegs as in some of the terrain I ride lower pegs would completely trap the bike between rocks rather than just scraping below the pivots. Ie across the bottom of the bike the lowest thing is the skid plate not anything else sticking down...

Share this post


Link to post
Share on other sites
 

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

×
×
  • Create New...