Hello, I changed out my tires and when I put the front back on the wheel is now locked up tight. I checked the little hole in the master and it appears normal and clear. Any advise? Probably need to remove calipers and replace seals? Also, this is on a 87FJ1200 with a R1 blue dot conversion. I have read on here that it is hard to bleed the fronts with the anti-dive set up which is still on there and seems to actually work a little too. Any hints on this? Thinking on replacing the lines with the RPM stainless lines at this time too. Riding season is slipping away in my area and the bike sits on a stand. Any help is appreciated.
The relief port in the m/c is plugged. Take the splash plate out of the bottom of the reservoir and clean out the bottom. When you squeeze the lever and release, you should see a small fountain of fluid return to the reservoir...Be careful with brake fluid, lot's of towels and a squirt bottle of water is a good idea to keep handy.
Still no worky? Then more cleaning is needed, disassemble the piston in the m/c and clean everything.
Might as well put new seals on the m/c piston while you have it out.
http://rpmracingca.com/proddetail.asp?prod=M%2FC%3AFRTBRKRBKIT (http://rpmracingca.com/proddetail.asp?prod=M%2FC%3AFRTBRKRBKIT)
If you don't already have one, order the extended reach snap ring pliers, trust me, you need these:
http://rpmracingca.com/proddetail.asp?prod=MasterCylinderSnap-RingPliers (http://rpmracingca.com/proddetail.asp?prod=MasterCylinderSnap-RingPliers)
So...what causes this relief port to get plugged? Gunk hiding below the splash plate along with
Old oem rubber brake lines which crumble internally causing problems like this.
http://xjbikes.com/forums/threads/why-you-need-to-replace-original-brake-lines-w-pics.41400/ (http://xjbikes.com/forums/threads/why-you-need-to-replace-original-brake-lines-w-pics.41400/)
Replace your oem rubber lines, they are long over due.
Hope this helps
Pat
Pat is probably right on the money. This is what happened to me a few months back, drove me nuts, rebuilt the calipers etc, and still locked on. There are actually 2 holes in the bottom of the master cylinder, my little pin hole relief port was hidden under a fine layer of sludge, cleared that and all good again.
Oohh found it. Here's what hapenned to me with some pics http://www.fjowners.com/index.php?topic=16291.0 (http://www.fjowners.com/index.php?topic=16291.0)
Quote from: whyzee79 on August 21, 2017, 04:33:19 PMI have read on here that it is hard to bleed the fronts with the anti-dive set up which is still on there and seems to actually work a little too.
Whyzee,
You can bypass the anti-dive units with nothing more than wrenches. Remove the short brake line from the caliper to the A-D unit by removing the banjo bolts. Use the short (one-line) banjo bolt to attach one brake line to each caliper. Done deal. If you want to remove the A-D units entirely, you would need block-off plates to replace them, and these plates must have oil passages for the fork oil. The block-off plates are about US$100.00 (if you can find them) so I just ignore the disconnected A-D units in place. I would doubt they work at all now anyway, and they were always more trouble than they are worth. All IMHO, of course. This little extra job will
not help your present problem, but it may eliminate a few headaches later.
I'd also recommend a new banjo bolt for the Master Cylinder-brake line connection, but get the one with a brake bleeder installed. That gadget makes bleeding the front brakes
much easier. The same banjo-bolt-with-bleeder is a good idea for the clutch Master Cylinder, also.
Re: Anti dive block off plates, a visit to our Suspension Files section will suprise you.
I experienced almost the exact same thing several years ago. After replacing the front wheel (while installing new tires, wheel bearings, front brake rotors and pads) I noticed that the front wheel was stiff when I tried to spin it while on the center stand and the front raised in the air. At first I thought there was a problem with the new wheel bearings but later figured out that the problem was with the calipers not fully releasing. After taking the calipers off I found out that the caliper walls were corroded behind the pistons preventing them from being pushed back far enough to fully clear the new rotors and pads.
Quote from: Pat Conlon on August 21, 2017, 07:42:19 PMRe: Anti dive block off plates, a visit to our Suspension Files section will suprise you.
Pat,
Okay, a pair of A-D block-off plates do not cost US$100.00, they only cost
US$99.00 so, my bad. Add a few more bucks for shipping, too.
:biggrin:
Ok, I'll order new hoses and a master caliper rebuild kit. I'll take it apart today and see what's under the little shield in the master. Probably should just order the o rings for the calipers too. I just find it strange that they worked fine until I removed the wheel. I didn't open any brake lines just removed the left side caliper. The right side stayed on the bike. Now it also feels like there is air in the system.
Whyzee, I would wait on the caliper seals. Definitely get new hoses and clean out the system and see how that goes.... lots of shit hides under that splash plate.
Red, you were right on for the price :good2: I just wanted you to know that the block off plates were not scarce, but readily available.
Quote from: whyzee79 on August 21, 2017, 04:33:19 PMHello, I changed out my tires and when I put the front back on the wheel is now locked up tight. Riding season is slipping away in my area and the bike sits on a stand. Any help is appreciated.
whyzee,
Looking back on your first post, I can not believe that you got the wheel back on (and the disk back into the caliper), and there is now any problem with the hydraulics. I can easily believe that the caliper should shift left and right, to center itself on the disk, and for some reason, it now does not do that. Try loosening the caliper mounting bolts, before you tear into anything else, and get the caliper shifting loosely on the bolts first. See if the brakes work normally then (do
not ride the bike like that, this is a
shop-only check). If that "fixes" the problem, forget the hydraulics and clean everything
mechanical that mounts the caliper to the fork, inside and out, first. You may be missing a spacer at the axle, or a spacer may be installed at the wrong location. I do not know the "Blue Dot" units, but that would be my $.02 worth. Once you get everything sorted, torque everything to specs.
It's always a good idea to take digital pictures as you loosen and disassemble things, especially on "modification" assemblies, because they will not be detailed in any book.
Update. I took off the little plate in the master. There is no crud under it (it looks spotless) and I took a small nylon poker and checked the little return hole. It spouts out fluid like you guys said it should. I removed the caliper that I originally took off and checked the operation of it. It seems two of the four pistons are not moving at all. I also took the other caliper off and all the pistons move nice and I cleaned them up when they were extended. I can probably get the stuck ones to extend. At this point if I can get them to move can I just clean them good and go about my day or is this a seal problem. I am definitely getting the lines after reading the info provided. About the anti dive. I understand taking the short hose off and using the short bolt but what about the fitting where the hose is bolted on the anti dive. I would think a copper washer and block off bolt are needed there too?
Quote from: whyzee79 on August 22, 2017, 10:16:44 PMUpdate. I removed the caliper that I originally took off and checked the operation of it. It seems two of the four pistons are not moving at all. I also took the other caliper off and all the pistons move nice and I cleaned them up when they were extended. I can probably get the stuck ones to extend. At this point if I can get them to move can I just clean them good and go about my day or is this a seal problem. I am definitely getting the lines after reading the info provided. About the anti dive. I understand taking the short hose off and using the short bolt but what about the fitting where the hose is bolted on the anti dive. I would think a copper washer and block off bolt are needed there too?
whyzee,
If you can get the caliper pistons moving, extend them a bit and clean the sides of the pistons with a green scrubber pad. If they are rusted and pitted, you will need a caliper rebuild. The only thing that retracts the brake pads from the disk after you brake is the flex of the rubber seals. If they have gone hard (not likely if the other seals are good), then you will need a caliper rebuild.
If you remove the short brake line from the A-D units, that will be fine. You can fill the hole with any short loose-fitting bolt, and seal it in place with some RTV sealant, if you wish. The fork oil will not come out of the hole, either way. Brake fluid should push a tiny piston to "harden" the front suspension, to prevent front-end dive when braking. The fit of that piston is far too tight to allow fork oil to leak - it must prevent hydraulic fluid under very high pressure from getting into the fork oil, when working as intended. I guess some rainwater could get into the open hole, but that would not affect anything in this lifetime.
Ok Red, thanks for the advise on the anti dive and the pistons. Ill post an update when I get a chance to clean them out.
Quote from: red on August 23, 2017, 12:15:30 AM
I guess some rainwater could get into the open hole, but that would not affect anything in this lifetime.
You can also flip the AD unit over on the fork... still provides the bypass feature and puts the adjuster knob on top so it looks like something functional. Also prevents the rainwater issue if there is one.
Frank
I think I will construct my own block off plates. Thanks for all the help from everyone involved. I have not had the time to fix this as of yet but at least have a plan of attack.
Something like this?
(http://fjowners.com/gallery/10/104_27_08_17_8_50_54.jpeg)
Quote from: whyzee79 on August 21, 2017, 04:33:19 PM
Hello, I changed out my tires and when I put the front back on the wheel is now locked up tight. I checked the little hole in the master and it appears normal and clear. Any advise? Probably need to remove calipers and replace seals? Also, this is on a 87FJ1200 with a R1 blue dot conversion. I have read on here that it is hard to bleed the fronts with the anti-dive set up which is still on there and seems to actually work a little too. Any hints on this? Thinking on replacing the lines with the RPM stainless lines at this time too. Riding season is slipping away in my area and the bike sits on a stand. Any help is appreciated.
Hi i dont think there is anything wrong with your brakes ..think about it, you changed your tire and your brakes was fine before you took off the front wheel right?.
Then something has gone wrong when you put the wheel back on .Mayby a spacer wrong way or speedogear stuck or wrong touque on the bolt.did you losen the front fender?Here is what i would do: take off the wheel again and check the bearings and the spacers.Then when you put it back just snug the caliperbolts and spin the wheel.If its spinning easy then spin it again and activate the brakelever so it stops several times if it spins easy after that start tighten the caliperbolts on right side(35nm) and check if its still spinning easy.Then you tighten the left side caliperbolts.Then tighten wheelaxle securing bolts .At last you tighten the wheelbolt to 78nm
Quote from: Old Rider on September 04, 2017, 12:11:46 PM
....then tighten wheelaxle securing bolts .At last you tighten the wheelbolt to 78nm
When you torque the axle bolt, the fork lowers slightly move.
For that reason (after the bouncy bouncy) the Owners Handbook says to snug up the axle pinch bolts last.
Suggestion: remove your calipers and spin your front wheel. Does it turn free? If so, then you do have a brake problem, if not then you have wheel bearing problem or something related to wheel installation. If you can define the problem you can more easily find the issue.
My 2ยข
Ed
I removed only one caliper when I did the wheel change. It does have the blue dot caliper conversion on it and the adapter plate so I went back to confirm that I put everything back right. It matched the other side with washer and plate so I removed it again and with the one side still on, it spins fine. I did the inspection and found that 2 pistons on the removed caliper were not moving at all. I have found a problem but have not had the time to fix it. I really appreciate the advise for assembly. I used to spin wheel and grab the brake a couple times before final torque. Is it best on this bike to just bounce the front end a couple times?
The piston cleaning didn't work real good. Now I notice that the PO has stripped the brake hose bolt probably using a standard wrench so the project is now getting more involved. Planning on resealing the bad caliper and the master seems mushy too even though it is really clean. You guys were right also about the brake lines. I had to cut them off in order to mount the caliper in the vise to remove the offending bolt and they were also really mushy feeling. Rubber was toast. Looks like a longer more involved fix then I was hoping for but got to be safe with the brakes. New winter project I guess. Thanks for all the help and I'll report when it is back in action. Now planning to order a bunch of goodies from RPM and do a real make over.
Ok so here is the update. All the caliper seals have been replaced. Still rubbing on the left side. I reread one of the posts and am going to try the bounce the bike then check again technique. If that doesn't work, I think a small shim on the caliper will help center it better on the disk. It is weird as if I just use the top mounting bolt and leave the bottom bolt off, it works perfect but if I do the opposite, it has interference which really doesn't make sense since this is the bolt without the adapter bracket. Arg again.
Hmmm.. top caliper bolt ok, but bottom caliper bolt no go....I wonder if your left stanchion tube is slightly bent?
Pull the fork tube off and roll it on a flat surface and check the run out (see if it wobbles)
I think it is something with this adapter bracket. The bike was working perfect prior to changing the tire. I think loosening up everything then checking is in order now. At least the brakes and tires are nice and ready to go. In the mean time I also picked up a really nice lower fairing that I was missing! It appears that the caliper body is making just the slightest contact with the disk. I can re-center the caliper with a small shim I believe but am going to try and get it to work like it was before I took it apart. The bike looks to have been down once so it is possible that the lower fork is bent but not thinking so as it was working in good order before but you never know. Anything is possible with a bike this old. I'm sure its something I am doing wrong!
After a careful look, I found that the adapter bracket wasn't exactly the same as the other side and it held the caliper too tilted back and it was contacting on the rear of the caliper. It also too several shims to get it centered but everything is good now. Just have to bleed the brakes but at least the front wheel spins like it should. I had to file a little off the bracket to tilt caliper slightly forward. The brackets were a home made bracket job from PO. They weren't quite cut and shaped right. Not sure how it was working when I bought it. Thanks everyone for the help.