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Discussion Starter #1 (Edited)
this is a bit of a cautionary tale about brake shoes de-laminating while driving, and the value of preventative maintenance checks.

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driving the bike last week, i had experienced what i thought was a momentary and severe loss of engine power while going down a long hill (with a turn at the bottom and a car behind me...).

it cleared, but i now think that it was in fact a chunk of brake shoe lining coming off and the sudden drag felt like the engine bogging. i resumed driving, the brakes dragged a little after that, enough to heat up, and i had to slack the cable off on the way home.

then, the other day, about 15 miles out, my front brake started grabbing erratically. i pulled over, removed the lever to give max slack, and headed disappointedly back home at half speed.

anyway, i got safely home, said a thanks to the various deities involved with the protection of fools and travellers, hoisted the bike up off of the rafters and pulled both wheels.

overall, i was surprised by how many little things had drifted towards becoming problems, and it's a reminder to be a bit more proactive on preventative maintenance. entropy happens.

here's what i found and did:

both front shoes totally de-laminated. back shoes fine.
i checked both sets under two years ago. neither appear to be oem, though only ~12k fairly easy miles on the 1990 bike.
no brand name on failed shoes, but numbers 3 y1-00 / jbd-41fg L.

i must say overall it's a really sweet brake design. simple, simple, simple.

tw_frbrake1.jpg

front tire preasure, = about 5 psi. rear = 20psi. i usually run both at 25-30 but had not checked them in ~3months even though i know the front has a slow leak. i know, i suck.

the low front air and maybe the dragging brake had worn a surprising amount of meat off the "just-out-from-the-centerline" lugs on the front tire. in retrospect it was handling differently, but i use the bike sporadically on varied terrain and it's surprising how much the front tire retains it's shape without much air. (it's a very stiff luggy "vee rubber 69r" made in thailand.)

tw_tirewear.jpg

continued
 

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Discussion Starter #2
continued

6 slightly loose spokes in rear wheel. under 1x turn (loose ones only) to take the wiggle out.

rear wheel weight (3oz stick-on) getting loose. cut it off, built a wheel holder and rebalanced. took 4oz, in the same spot.
that seems alot for a small wheel. 13-14" car tires generally take less than that.

the ideal way is to do balancing is on just the rim, mark it, then install the tire's heavy side opposite the rim's heavy side. use less weights that way. for my truck, i have a spare front hub with no grease and no seal, lubed with light oil , mounted to a bar which i put in the vice and balance all my rims and tires on that. the rims are numbered and marked re their balance, and i selected the two truest rims for the front end. 31/10/15's and it's worked out well. down to 1/4 oz. to hell with paying for that !

the rear bike rim had a runout of about 1/16" side to side.

the front tire had an existing 1oz weight on a spoke. it took another 3oz in the same spot. again, seems like a lot.
the front rim had a runout of about 1/32" side to side and over 1/16" up and down. i can see that as i drive but it's never seemed to be an issue. big luggy tire under 60mph.

tw_wheel_bal.jpg


both actuating shafts for the brakes were dry, and the rear was just starting to stick. removed, cleaned, greased.

cleaned shaft seal at speedo gear, greased gear and seal, removed speedo cable, which was getting dry, and lubed with chainlube.

speaking of potential wheel lock-ups, the long rear sprocket bolts have always seemed to me like trouble in a chain derailment situation, as the chain could fit in under them. ideally one would have a rubber or cast flange that fitted over or under the bolts. instead, after checking bolt torque, i oiled the area and then packed the area with construction adhesive which sets up fairly hard.

tw_sprocket_bolts.jpg

tw_sprocket_bolt_glue.jpg


which turned out to be a clunky hack but it only cost about a buck so i'll go with it for the moment. maybe some black paint. hides a multitude of sins.

installed new shoes, reassembled everything, thanked the deities in advance for my 4 hour road trip for tommorrow...

slowmod
 

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Discussion Starter #4
Ride-On works very well for balancing, plus the flat protection.
that's interesting to hear that. i 've never used it, but i researched ride-on a couple years ago.

could never get my head around the actual mechanism of how it worked. seems to me that centrifical force is gunna send it to the outermost spot inside the tube/tire, period. in the case of my front fim/tire with a 1/16"+ bump out, it's going to gather there more, whether of not that's the heavy spot. in fact it would tend to be already functionally heavier _at that spot, as it's farther out from the axis.

maybe the ride on works partly by dampening out vibrations, and thus settling things down. i like the flat protection aspect. am curious to try it out at some point.

cheers, slowmod.
 

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When I first got my bike, of course being an 87 with original tires, they had to be replaced immediately. I had the dealer mount up two brand new tires and balance them. It came back with 5 oz. on the front and it almost hopped down the road, it was so bad. They couldn't get it right. I pulled all of the weights off and put in Ride-On. Smooth, smooth, smooth. Nothing. Absolutely perfect and not a problem since. Ride-On is kind of like tiny tiny beads or grit in a solution of sludge. It goes where it needs to be and works very well in my opinion. I went with the heavy duty application which uses a little more, if I remember correctly. I bought 3 little bottles and I think it was about 50 bucks. In a tubeless tire, I would think it would be 100% effective in sealing a reasonable leak, but with a tube like we have, it might be hit and miss, depending if the tube sealed ok, but still, I think it is worth it.
 

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Discussion Starter #6
"It goes where it needs to be"

yes, but how. that's what i want to know. what is the mechanism? does the "thump" of whatever is out of balance cause the goop to vibrate away, and thus balance? hmmmn.
 

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Slow, If a tire moves in ANY direction out of its true circumference the ride on will go to the exact opposite direction of that movement, even if its side to side like you say your wheels are.

Think of it like this, you (your the ride on) are in your car (the car is your tire) and stopped at a traffic light. You get rear ended by another car. Your car (the tire) lurches forward, what happens to you (the ride on)? You try to move to the back of the car in the exact opposite direction of the car movement. This is what happens to the ride on and why it works so well, weights only work at the time of balancing and start becoming unbalanced as soon as you start wearing rubber away. And weights cant take into account any side to side movements. Ride on takes care of ALL movements and continues to take care of them as the tire wears and is why LT says its butter smooth.
 

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ill put in another recommendation for ride-on. I have it in all my bikes and i have noticed the balancing aspect works well. It straightened out my Duro power grip that i could never seem to get right and its now very smooth at speed, my fronts on both of my TW's are also wearing very well with less cupping. I have never had to try the sealing properties of it yet, hopefully i never have to.

Here is a video on how it works.
 

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Discussion Starter #10 (Edited)
Slow, If a tire moves in ANY direction out of its true circumference the ride on will go to the exact opposite direction of that movement, even if its side to side like you say your wheels are.

Think of it like this, you (your the ride on) are in your car (the car is your tire) and stopped at a traffic light. You get rear ended by another car. Your car (the tire) lurches forward, what happens to you (the ride on)? You try to move to the back of the car in the exact opposite direction of the car movement. This is what happens to the ride on and why it works so well, ..

ok, that part makes sense to me, as in the case of, say, a wheel/tire with a physical side to side runnout. the ride-on is a separate mass that is resists changes in trajectory, and that counteracts, "balances against" the deviation in trajectory of the wheel/tire.

as well soft materials absorb vibration better (steel bad, rubber good, slime best...)

this would be dampening, not balancing.

the energy would still be generated, it's just being absorbed better.
which is probably why the affect doesn't "show up" on balancing machines. (as i recall reading?)

dampening definitely has it's uses.

my sense is that ride on/slime/balancing beads is a great tool to have in the toolbox, as it were. just trying to figure out what tool it is.

if i were to use it, it would be after already static balancing the wheels and then the installed wheel/tire. basics first, and it's easy and cheap. on my truck, i had a rim that was 4oz out, installed the tire, it was now 8.5oz out. spun the tire 180deg, .5oz out. a better place to start from.



..weights only work at the time of balancing and start becoming unbalanced as soon as you start wearing rubber away. And weights cant take into account any side to side movements. Ride on takes care of ALL movements and continues to take care of them as the tire wears and is why LT says its butter smooth.

dynamic balancing balances for side-to-side.

my guess and limited experience is that side-to-side _weight variences (as apposed to latteral runnout) is much less important than _weight variences in the the rotary balance, which is then multiplied by centrifical force.

so, yeah, interesting, thanks. your car analogy was actually the most scientific explaination of ride-on that i have seen. i put in about 5 hours reading up on it a couple years ago.
 

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Yes weights can take care of a lateral imbalance, I was speaking more of how WE balance our on MC tire on a balance stand. And even at shops with a dynamic balancer it has much less affect because the tires just arent wide enough. But even that small amount ride on or dyna beads can take care of it. And as far as balancing the tire first, unless your talking about only matching the heavy part of the tire with the light part of the rim, I wouldnt do it, no need to and I think they advise against it.
 

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About your brake shoes. I've seen after market ones do just what yours did but have never had any problems with O.E.M. ones from Yamaha. I've tried EBC shoes and did not like them at all!! No stopping power and they squeeled. Guess the squeel was a built in feature to warn people to get out of the way.
 
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