TW200 Forum banner
  • Hey Everyone! Vote for the Site Favourite BOTM winner for the year of 2022 HERE!

Front-rear imbalance in load causing poor handling?

8K views 77 replies 22 participants last post by  jb882 
#1 ·
Anyone else feels that the more weight you add to the back of the tdub, the more unstable the bike becomes?

I could be considered a feather-weight rider I guess at 115 lbs.

I have a heavy setup of racks and luggage at the back. On the front I am now with a Golden Boy and a ultra-heavy duty tube.

I recently found out that the closer I move to the front of the bike on the seat, the more my front wheel feels plant to the ground. But this seating position is quite uncomfortable in the long run.

Generally, I can't feel comfortable on gravel unless I use that seating position. Pushing hard on the handlebars seems to make me feel more secure as well. But it's an impossible way to do your riding hey...

At high speeds (over 90km/h) I've had enough wobble warnings to become very conscious of my driving.

First one happened when I had a pipe wrench in one of my cases. I loaded the bike with no after-thought and all the heavy stuff may have been on that side. It took strong wind gusts and longitudinal cracks on the asphalt to start the oscillation. Happened again a minute of two right after. I now call this "the pipe wrench effect" 😄

I changed my front tire again, just in case. But it's happening again with the Golden Boy.

I really suspect an imbalance in suspension between the front an the rear.

Thoughts? Stories?

I need the luggage space back there. My bike is my car at this time of year. I don't see how I could add more load to the front. And would it help anyway?
 
See less See more
#9 ·
You need to distribute the weight more evenly around the bike and learn to sit nearer to the gas tank
 
#13 ·
In your case a front rack would help, get one that goes over the light so nothing will interfere with the light and move some tools up front and some on the rear. Shift your weight up front and get used to hugging the tank with your knees, this will shift weight over the front which is exactly what you want and the bike will feel much more stable. Have you lowered the front or rear? Or changed shocks or anything? What air are you running in the tires?
 
  • Like
Reactions: Scooterbrained
#15 ·
No tampering with suspension. I tiptoe my way on this bike and I prefer that to changing the geometry of the machine. I run my tires around specs (18-18). Tried harder cause I commute mainly on pavement but I felt so poorly grounded that I had no fun at all.
 
  • Like
Reactions: littletommy
#16 ·
Is there any chance of moving your luggage, or at least some of it, just forward of the rear axle? Quite a bit of difference between that and it hanging past the rear axle.

Marty
 
#32 · (Edited)
Is there any chance of moving your luggage, or at least some of it, just forward of the rear axle? Quite a bit of difference between that and it hanging past the rear axle.

Marty
This. At 5'2" (unless you have freakishly looong arms & legs) you're most likely already sitting up on front of seat, therefore getting to Marty's point....you have some available real estate on the seat. Whatever you're carrying back there, may start with the heavier items, and move them forward, as long as they can be placed securely.

Start experimenting.
 
#18 ·
Do you carry fuel or water? If so, they can ride up front in RotoPax jugs on a Cyclerack front rack. I carry a gallon of water and a gallon of gas up front and it balances out a bunch of weight on the rear.

PS... It also makes the front end kinda heavy and some folks would not like that. Doesn't bother me.

Sent from my Pixel 3a XL using Tapatalk
 
#20 ·
Funny cause I thought about that. I only fill my Rotopax once a week so that doesn't count and plus it's on my tail rack.

Upon reflecting on my growing concern with stability, I thought about getting the front rack and carrying water in a Rotopax just for the sake of giving my front wheel more grip.
 
#22 ·
I have balancing beads. The tire is bumpy at low speeds but we figured it's from poor building. It's well seated, nice and even. You could say I miss the Anakee...
 
#24 ·
#51 ·
I carried too much stuff in backpacks in my life. Gee I'm getting old. 😄 I figure if I'm going to burn gas, I might as well let the bike do the work for me.

I hope I pictured your suggestion well here and so that the answer is relevant.
 
  • Like
Reactions: Scooterbrained
#28 ·
when i first got my tw i experienced some scary speed wobbles at highway speeds. my steering bearings were a bit worn, and i was running ~30+psi in both tires. in cars and trucks, i generally like the crispness and effeciency of keeping tire preasure up. i run the rears close to max rating, and then drop front pressure a bit till it settles.

after getting rid of the bearing wobble, and a bit of front brake drag from a sticky cable, a new tire, and balancing my own tires - easy - adhesive lead weights, and you can also check the run-out (wobble-deviation) on the rim and/or tire, i never get those wobbles anymore, maybe a taste if one hits road weirdness or something.


one wants to get rid of things that generate inherent instability or allow it to build. for instance, if your rim is an ounce out, and your tire half an ounce, and they end up mounted so they add not cancel.. personally i'm suspicious of tire beads/slime, etc. centrifical force is gunna send them to the outermost spot, which may or may not be where weight is needed. i haven't used them though. address the basics - bearings tight, runnout, balance, tire pressure.

what tire matters, and what combo of tires. i've mostly run the stock tw dirt tires, though mostly on pave.

22 front, 30 rear.

i weigh 150, and i routinely carry say, a 20litre water bottle, plus tools, plus beer, on a rear rack, entirely aft of the seat. i compensate forward a little, but not much.

racks on the forks will mean slower steering response, and catch crosswind.
 
#30 · (Edited)
A couple of questions i have. First is how does it feel at slow speeds? Second is does it do the high speed wobble with just you and no luggage? If you have never tried the bike at speed with no luggage you may have to do that to rule out chassis issues.

If it does the high speed wobble or tankslapper unloaded you may well have a chassis issue. in this case I would start with the steering stem bearings as oldword 124 mentioned..... Bad steering stem bearings will definitely cause tank slappers to happen. Not only would i check for stifness i would check for lateral pay when you have it off the ground.

Also check the rear swingarm bushings. Just like the stem bearings bad swingarm bushings will cause tank slappers as well.

Lastly, tires, check the balance.

If the chassis is fine with the bike unloaded then you have to look at the weight you are carrying. How much total weight are we talking about here? in my experience the TW can carry a fair bit of weight but stability can definitely suffer. What you may be looking at to fix it in that case is less weight, or a stiffer rear spring or both. You can also try raising the forks a couple of mm in the trees but that also changes the steering geometry a little and can make it twitchy.

A little story, we recently took a trip on our TW's and i definitely experienced some stability issues with the bikes due to the weight we were carrying.

This is what our TW's looked like loaded up with everything we needed for 6 days of camping, clothes, food, tent etc.


Needless to say the bikes did not handle very well at all with this much weight on them. As they sat both bikes have the white pro cycle spring on them so they were already better equiped to handle weight than a stock bike. Her bike was set to the lowest preload setting mine was set to the middle. Both bikes i barely got out of the garage before i was like no way we are riding these all the way to the Canadian border like this. The front felt like it was going to wash out on any corner just putting in the yard and on the street at like 20 mph the bike was super sketchy.

I ended up having to take the shocks out and set the preload to max on both to get them rideable. In her case because she is lighter than I at 125lbs the bike was great for her. Mine was ok too but at 185lbs i wish i still had the heavier red spring on mine but the white one at max preload was rideable for me. There is no way we could have put this kind of weight on them with stock springs.
 
#47 ·
A couple of questions i have. First is how does it feel at slow speeds? Second is does it do the high speed wobble with just you and no luggage? If you have never tried the bike at speed with no luggage you may have to do that to rule out chassis issues.

Will be testing it more as I'll be on vacation for a few days. I think that unloaded, the effect I will feel the more is the knobbies of the Golden Boy at high speeds.

If it does the high speed wobble or tankslapper unloaded you may well have a chassis issue. in this case I would start with the steering stem bearings as oldword 124 mentioned..... Bad steering stem bearings will definitely cause tank slappers to happen. Not only would i check for stifness i would check for lateral pay when you have it off the ground.

I don't know what loose bearings feel like, but I just bought a 1999 and I think she has the condition. Something feels wrong in the steering. So my 2020 would be okay. To be confirmed.

Also check the rear swingarm bushings. Just like the stem bearings bad swingarm bushings will cause tank slappers as well.

Lastly, tires, check the balance.

If the chassis is fine with the bike unloaded then you have to look at the weight you are carrying. How much total weight are we talking about here? in my experience the TW can carry a fair bit of weight but stability can definitely suffer. What you may be looking at to fix it in that case is less weight, or a stiffer rear spring or both. You can also try raising the forks a couple of mm in the trees but that also changes the steering geometry a little and can make it twitchy.

I don't usually carry that much weight really. I just don't limit myself. If I need extra gear I throw it in.

A little story, we recently took a trip on our TW's and i definitely experienced some stability issues with the bikes due to the weight we were carrying.

This is what our TW's looked like loaded up with everything we needed for 6 days of camping, clothes, food, tent etc.


Needless to say the bikes did not handle very well at all with this much weight on them. As they sat both bikes have the white pro cycle spring on them so they were already better equiped to handle weight than a stock bike. Her bike was set to the lowest preload setting mine was set to the middle. Both bikes i barely got out of the garage before i was like no way we are riding these all the way to the Canadian border like this. The front felt like it was going to wash out on any corner just putting in the yard and on the street at like 20 mph the bike was super sketchy.

I ended up having to take the shocks out and set the preload to max on both to get them rideable. In her case because she is lighter than I at 125lbs the bike was great for her. Mine was ok too but at 185lbs i wish i still had the heavier red spring on mine but the white one at max preload was rideable for me. There is no way we could have put this kind of weight on them with stock springs.

I'm loving this "compte-rendu" of how you managed to make it possible although the bikes don't look like they were designed for the job.
 
#31 ·
#44 ·
Take all the stuff off the bike rack, take it for a ride - if it handles well - it's your stuff on rear rack. Rides poorly, you have another issue.
I've carried heavy loads with no issue
Are you a lightweight person Donzo?
 
#34 ·
All your inputs are highly inspiring. I am considering drilling new holes in my paniers to bring them a couple inches forward. Never thought of that option. They do extend behind the rear axle as it is. I'ld make sure they don't get in the way but with the new seating position plus my mini size it should be ok. Low side tank bags would make the front end feel heavier without loading the fork directly. I had shopped for those but never ordered.

More comeback later. Lunch break over :)
 
  • Like
Reactions: littletommy
#36 ·
Hey, good advice on comparing unloaded to loaded performance, also ensuring your rear suspension is configured to handle your max loaded weight and you run the air pressure that best balances your bike.
If you superimpose a triangle over the side profile of your bike, utilizing the front and rear axles as the lower points and the top of your head as the apex you want, need, to have all the weight possible inside that triangle. This will allow the bike to operate at its best.
Also, the more you can stay "on the power" the better your bike can handle a loose surface such as gravel or sand as it "loads" the rear suspension, this may require running a lower gear than normal to control speed.
For me, it's much easier to handle these surfaces while standing as it allows controlling the bikes direction by tiny balance inputs through the pegs.
Sounds like a great excuse to do lots of focused riding! ;-)

Bag
 
#55 ·
I like the triangle image. I will keep it in mind.

The "on the power" image I'll have to experiment, although it's the front wheel that I feel loose on gravel.

With all the info in this thread, I have plenty of material to focus on for my next loaded and unloaded rides!
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top