There are a few in our club but not sure how many have been sold. It can't be more than a handful. To think that selling new look-a-like bikes directly against one to two year old premium bikes at a cheaper price does not drive down the used prices is naive. I feel that I practically gave my 2 year old pro away.
Pistons seem to be moving fine. However, the disc rubs the inner (stationary) brake pad. I'm guessing I need to shim the caliper at the fork mount to move it slightly inboard, so that the disc sits off the stationary pad. It does have a floating disc, but no slop to keep it off the pad as currently mounted.
The disc should run in the centerline of the caliper. There is no stationary pad, both should move. It`s been since about `93 that we worried about spacing on a gasser.
Just re-read the post. Have you even ridden this yet? Did you adjust the lever settings yet? Does the bike stop? Do you know how to break in a front brake in 5 minutes at home? I am just trying to help, I just finally read between the lines.
If I get your meaning, my eco has this issue if I center the bearings in the hub of the front wheel. Seems kludgy, but the wheel can be offset a little to align the disc in the caliper.
Thanks for jumping in there John, work calls! Have to be in Roswell for the last 2 day vintage!!!! 5 am I`m out of here.
Do you mean that this is common, or that it ceased to be common? Run along, you can answer next week !
Ok, i deserve that - 2 pistons on each side would make it awfully hard to have a stationary pad. I must have convinced myself that the pad had to be stationary with how far off the alignment of the caliper was. Moving on. Answer to all of the above is yes. Hadn't noticed the drag at all while riding. Only picked up on it after i noticed the front wheel wandering, and tried to spin the wheel after raising the bike to start truing the front rim. So this may be due to wheel spacers that were incorrectly installed?
Spacers are probably fine. They are one size fits all. Graydog had to slug the bearings over about 3/16" to make the wheel center. The bearings have a tube between them, that the axle tightens down against. It you pound on the bearing with a wood block and a big hammer, you can drift the far side bearing out a bit, thus recentering the wheel. Based on the Fixed pad and wheel truing comment I am guessing you have Mountain Biking background? Spend awhile working lube down into the nipples before trying to true. Gas Gas does not use nearly enough antisieze when they assemble the wheels.
I have a 12, no issues except for excessive chain drag on the top chain guard. Starts easy, runs great. Doesn't feel heavy. Lot better bike than I need....seems more stable than my 03 was, easier to ride than my montessa was......just wish I had more time to ride......remember to check the spokes and go.
Regarding disc and caliper alignment discussion, I didn't follow it entirely. Some of your comments on alignment puzzled me. Here's why: Trials bikes, with no or few exceptions, employ a simple brake scheme that fixes the caliper body to the fork leg and floats the brake disc at the disc attachment to the hub. The fasteners limit out on cylindrical dohickeys that allow slop at the hub connection. Grab the disc and give it a shake and you'll feel and hear the slop. Unless some of you have an unusual front brake caliper on your Eco, there is no fixed side to the brakes with respect to pads and discs, as lineaway pointed out. You should see bulges in the caliper casting for four pucks, two on each side. The fixed brake calipers then have additional lateral compensation or float by having pucks or caliper pistons in both halves of the caliper body (on both sides of the disc). This is the hydrodynamic float. The pistons will compensate for pad wear and maintain even clamping pressure. As long as the disc does not contact the caliper casting and make squeaky noises from the contact, even if the disc in not centered in the caliper, the pucks will compensate. The only time being offset a little will matter is if you wear your pads almost completely out and the pucks on the one side are extended far enough to cock slightly in their bores. But you all wouldn't let pads wear to the metal, right? My `10 Econo uses a standard version of a 4-puck AJP brake caliper still used on some brands on their 2013 models. They are slightly stronger in stopping power for some reason than my Raga's AJPs with the wing-flared caliper castings. Both AJP versions use the excellent Galfer Red pads. All hydraulic disc brakes require lateral float to prevent problems. Some motorcycle brake designs float the calipers on rubber-boot-sealed pins and fix the brake disk. These designs tend to have caliper pucks only on one side of the caliper. As the pads wear, the pucks and pins keep things centered. If you do have an oddball front brake many would like to see it! Please post a photo of your oddball brakes which include a closer-up view of the caliper from the top.
Using the center tube to move bearings is asking for trouble.All the pressure is being put on the balls and cage which is the weakest and most vulnerable part of the bearing.To move a bearing you really should tap on the outer shell.That is the only part of a bearing that is strong enough to push sideways.
This is the first I have ever heard of "centering" wheel bearings to true up a wheel. :huh The bearings should bottom into some kind of recess in the wheel, que no? It maight have been done on some POS english bike back in the day, be we are talking about a modern bike.
Graydog, I think he's talking to you... If I remember correctly, your disk was dragging on the caliper? Fair point about hammering on the bearings. But how do you extract a bearing without hammering on the center? I have a bearing slide hammer that works well for pulling them out, but pulls on the center. Once you have one side out you can reach through with a punch and get at the far side outside rim. But, if you are looking for a fairly small amount of displacement, that sounds like alot of work, and you are still putting a bunch of pressure on the center of one bearing. I have never had one come apart, and they have all still turned without issue when I toss them in the emergency box. I think for the low stress trials environment, the bearings may be good enough. The gas gas wheel bearings don't have bottoming lips. If you keep pounding on it, you can push it all the way through the hub. Tap one side in to flush, place the center tube, tap the other side in, place axle, pop into the forks, tighten everything together. The first time, I tried to hold the center tube in place, while tapping. Lost a little skin to the center tube, then to the hammer, in short order... :huh Lets say things were said.
Gordy, this is kinda what Mike Carlton said. It's not truing, so much as centering the hub in the forks so that the disc is aligned in the caliper. I discovered this when I had the wheel off for a new tire, probably two years into the life of the bike. The bearings weren't exactly the same in the cups, so I put them so. Upon reassembly, the disc dragged in the caliper. By trial and error, I returned the bearings to the offset position, probably 1mm in on one side, out on the other, and have kept it that way. This summer the bearings went wobbly and I replaced them. Possibly this is from rough treatment, but heck, five Ute Cups for twenty bucks in bearings...
Que si! The hubs are designed to have the internal spacer the same length as the space between the inner races when bearing outer races bottom against the counter bores in which they are pressed. That is why they have no snap rings. If a hub has no stops for the outer races, that is definitely NOT right and not a general characteristic of GasGas (AJP). If true on a bike it is a rare exception, not the rule. Bearings are typically pounded out by their inner races. You have to cock the spacer to get at the inner race, then go around radially to knock out the bearing evenly. If done with many smaller taps (no brutally) and evenly to prevent the race from cocking and sticking, the races and balls typically won't Brinnell (dent). But there's no reason to remove bearings if they are not really trashed. Just pop the seals off, spray them with brake cleaner to break up the grease, and use a air hose to blow out the crap. Re pack them solid and they'll last the life of the bike. If you do have to replace them with new ones, you all should still pack them solid or they'll get water in them and eventually get rusty mud and degrade.
"Bearings not the same in the cups." Interesting! That could only be from a machining error on that particular hub where the bores were machined too deep on both sides! Possible, but rare.
Repack them solid? Guess there is less chance of heat issues on a TB, but I've read several discussions re this on trials boards and heard from more than one gear/bearing specialist engineer that solid is too much. And certainly to not open up new bearings and fill them up. That the manufacturer does not pack them solid because they are trying to save costs, but rather they put in a lesser amount because it is the right amount, all things considered. What I heard, YMMV I am sure to hear. And here's a tip for bearing removal (for the shade-tree mechanics among us) when you can't dislodge the delicate alloy spacer and there is no notch in it to get a proper purchase on the inner race; get the HF Blind Hole Bearing Removal Tool! It is only $50 and will pay for itself after only ten years of using chi-com bearings instead of real ones.
