My XR650L conversion

[6bt]

Nice man, where at in NY?

Sent from my XT1254 using Tapatalk

[fabiodriven]

Nice man, where at in NY?

Sent from my XT1254 using Tapatalk

I live in Massachusetts actually.

[fabiodriven]

I'm getting this pig back together and I realized my shock linkage was contacting the swing arm preventing me from being able to get the swing arm back on without force. I remembered the tolerances were tight when we built this swing arm, but nothing was hitting. It then dawned on me that I removed the factory XR dog bone and installed an adjustable lowering link months after the swing arm was built. I must have just crammed it in there thinking I'd deal with it later, so I did. It wasn't hitting when the suspension compressed, but rather at full droop. I had to massage the swing arm slightly then throw a quick bead on it where I had removed material.

The stripping and painting went well but this machine will never be a show bike. The head pipe looks 1000% better and I replace much of what I disassemble with stainless hardware as I reassemble. I'm looking forward to riding it down the road again soon.

One problem I've had the entire time I've owned this machine is a soft front brake. No matter how I bleed it or what I do, it is always soft. The system consists of the 2002 XR master cylinder (possibly original) and 1985 Tecate line and caliper. Today I took the caliper off and held it up in the air over the bike while I bled it, I gravity bled it, and I even pushed the fluid back up from the caliper to the master multiple times, this thing will not build pressure. I don't like playing guessing games, but I don't have many clues. It does not "bleed down" if you hold the brake, it will hold pressure for a very long time if not indefinitely if you hold the lever to the bar. The system also doesn't leak anywhere. These two clues tell me that it's unlikely (but not impossible) for the problem to be the master, and it's likely not the caliper I'm thinking (but don't know that either), so I'm assuming (but don't know) that the brake hose is compromised in some way. It's not bubbling obviously or anything, but I'm thinking it might be old and weak enough to flex. I'm open to suggestions though if anyone has dealt with a similar issue.

Thanks for reading.

[Rob Canadian]

Hey. wonderboy was having a issue with his 350X with soft brakes. 2nd page. Other links int he thread also.

http://www.3wheelerworld.com/showthr...5-350X-Rebuild

[fabiodriven]

Hey. wonderboy was having a issue with his 350X with soft brakes. 2nd page. Other links int he thread also.

http://www.3wheelerworld.com/showthr...5-350X-Rebuild

That's the thread I was looking for, thanks a lot for posting that. I knew I'd seen something recently on here but couldn't remember the thread.

[wonderboy]

I haven't figured mine out yet, otherwise I'd try to post something helpful...

The thing I want to try is to test the lever feel one step at a time. So first thing will be to bench bleed the master, then plug the outlet up solid with a bolt and check the feel. I want to make sure the master is building pressure solid and holding (no leakage past the piston).

Next, I want to isolate the hose. So the plan next would be to attach the brake hose and figure out a way to purge the air and then block off the caliper end of the hose. Repeat the 'feel' test.

Finally, (assuming the other tests pass) it will be time to connect the caliper and see if that is the culprit. I have a feeling that I somehow (despite my many attempts) have air trapped somewhere inside the caliper. We'll see.

If I come up with any revelations, I'll post them up.

[fabiodriven]

I haven't figured mine out yet, otherwise I'd try to post something helpful...

The thing I want to try is to test the lever feel one step at a time. So first thing will be to bench bleed the master, then plug the outlet up solid with a bolt and check the feel. I want to make sure the master is building pressure solid and holding (no leakage past the piston).

Next, I want to isolate the hose. So the plan next would be to attach the brake hose and figure out a way to purge the air and then block off the caliper end of the hose. Repeat the 'feel' test.

Finally, (assuming the other tests pass) it will be time to connect the caliper and see if that is the culprit. I have a feeling that I somehow (despite my many attempts) have air trapped somewhere inside the caliper. We'll see.

If I come up with any revelations, I'll post them up.

That's solid, that's exactly what I'm going to do. My neighbor was here when I was working on it and he said "Well can't you just replace everything?" I told him yes, and normally I don't mind part swapping because worst case scenario is I end up with new parts on my bike and a spare for the shelf. Unfortunately I'm working on a ton of things right now, all of which need funding. I'm going to have to diagnose this one first and replace only what I have to.

I like your plan and I'm going to do the same thing with mine. I suspect the line but realistically it could be anything. Thanks very much for the post, I'm glad I posted this issue. I almost wasn't going to bother posting about it.

[fabiodriven]

I bench bled the master cylinder today and was able to get a firm lever with the line removed and the outlet blocked, so I know the master is good. I then reinstalled the line and caliper and could no longer get a firm lever regardless of how much I bled the system or sent the fluid back up from the caliper. I then crimped the line close to the master cylinder and got a firm lever. I then crimped it down near the caliper, and again, firm lever. With the caliper in the system, it goes soft. It is slightly odd what it's doing, I don't know what's wrong with it yet.

I'm theorizing that the piston is getting hung up on the seal in the caliper, so it goes out when the brake is applied but rather than staying put it looks like the seal is pulling the piston back in? Retracting it so to speak. I'm not even positive this is my problem. Honestly it feels too spongy to really support that theory, but I'm at a loss. I bled the crap out of this thing today, like plenty. I'm really at kind of a loss.

I'm disappointed that my Eastwood exhaust manifold coating started cooking right off the head pipe as soon as I started the bike. It worked great on the steel 225DR head pipe, but this one is stainless. I think that's the problem. Whatever. My stuff is just polished turds anyways, I don't do show bikes.

[coolpool]

I haven't figured mine out yet, otherwise I'd try to post something helpful...

The thing I want to try is to test the lever feel one step at a time. So first thing will be to bench bleed the master, then plug the outlet up solid with a bolt and check the feel. I want to make sure the master is building pressure solid and holding (no leakage past the piston).

Next, I want to isolate the hose. So the plan next would be to attach the brake hose and figure out a way to purge the air and then block off the caliper end of the hose. Repeat the 'feel' test.

Finally, (assuming the other tests pass) it will be time to connect the caliper and see if that is the culprit. I have a feeling that I somehow (despite my many attempts) have air trapped somewhere inside the caliper. We'll see.

If I come up with any revelations, I'll post them up.

That seems like the most logical test of your components. You could step it up one more notch and install a pressure gauge to get an actual number to compare each components performance with, but unfortunately this will cost some money. And I'm not sure what a pressure range for the gauge gauge would need to be?

[atctim]

Hey Fabio: What carb do you run on your bike, and can I see a picture of your air intake set up please?

I need to order a new carb to get mine to run right - the stock carb will not rev out with non-stock intake. I have re-jetted to the moon and back with no changes to the not reving out issue. Honda had to build this intake system very finicky to pass all 50 state emissions (Thanks California Legislators - you bunch of morons!). I want to be able to rev it out - but can't.

[fabiodriven]

Hey Fabio: What carb do you run on your bike, and can I see a picture of your air intake set up please?

I need to order a new carb to get mine to run right - the stock carb will not rev out with non-stock intake. I have re-jetted to the moon and back with no changes to the not reving out issue. Honda had to build this intake system very finicky to pass all 50 state emissions (Thanks California Legislators - you bunch of morons!). I want to be able to rev it out - but can't.

My carb is stock as far as I know Tim. The bike has a White Bros. silencer which is loud, and it has a pod on the intake. It's a bit grumpy off idle as far as jetting goes, not bad enough to be of too much concern, but it opens right up. I have no issues whatsoever with power. The EGR is gone but I kept that ugly canister on the bike. Someone told me not to get rid of that, possibly Louis.

Forgive the filthiness of the bike in the pictures, it's getting washed soon. I registered it today but I still have to finish assembly as well as figure out what the issue is with the front brake.

[HairyJR]

John hope you solved the starting / running problem. If not I may not have been clear in one of the previous posting talking about handle bar on/off start button switch, found the internal contacts dirty and corroded.

Now onto your current problem with bleeding caliper. You are correct in that piston/puck retracts a tiny amount caused by the O-ring / quad ring rolling back. Had a past experience with a caliper seized and didn’t float therefore actually bending and deflecting the rotor disc, by doing this caused the piston to travel further. I see the supply line has a loop where it connects to the caliper, believe it or not but there’s air still trapped in the loop, high spot. The reservoir pressure doesn’t supply enough volume to push the air bubbles down the line. Same issue applies to hand held bleeders. Straighten the line to bleed either by removing reservoir or caliper. Because the piston retracts one time as a final resort used a “C” clamp to hold piston all the way inserted limiting any movement in order to bleed it successfully. Have always had better luck reverse feeding bleeding. Frustrating problem…..

"HJ"

[fabiodriven]

John hope you solved the starting / running problem. If not I may not have been clear in one of the previous posting talking about handle bar on/off start button switch, found the internal contacts dirty and corroded.

Now onto your current problem with bleeding caliper. You are correct in that piston/puck retracts a tiny amount caused by the O-ring / quad ring rolling back. Had a past experience with a caliper seized and didn’t float therefore actually bending and deflecting the rotor disc, by doing this caused the piston to travel further. I see the supply line has a loop where it connects to the caliper, believe it or not but there’s air still trapped in the loop, high spot. The reservoir pressure doesn’t supply enough volume to push the air bubbles down the line. Same issue applies to hand held bleeders. Straighten the line to bleed either by removing reservoir or caliper. Because the piston retracts one time as a final resort used a “C” clamp to hold piston all the way inserted limiting any movement in order to bleed it successfully. Have always had better luck reverse feeding bleeding. Frustrating problem…..

"HJ"

Good to hear from you Hairy!

I suspected something with the on/off switch as well, but the thing with that is if there's a problem with that switch the bike will not crank. It won't crank with that switch in the off position and it also doesn't crank if unplugged. This machine does crank, it just doesn't start.

As far as the bleeding goes, I had the entire system off the bike, master in the vise and caliper on the floor, line straight with no loops. It doesn't matter what you do. I can force the fluid up backwards from the caliper to the master, it doesn't matter. Ironically enough, I tried exactly what you suggested today. I collapsed the piston all the way in and bled it like that, no improvement. I bench bled the master and it bled out perfect. I crimped the line near the caliper and it's still firm. If I include the caliper in the circuit it goes soft every time, it doesn't matter how it's bled. I still don't understand what the problem is but it will not work correctly. I bled it for a very long time yesterday and again today, it won't firm up.

It's an 85 Tecate caliper so I don't really know what to do now. I don't think they're available nor was I able to find a rebuild kit. The piston and caliper itself look fine and it doesn't leak. I'm just guessing at the seal being a problem because I have no friggin idea what else could be wrong.

[HairyJR]

Well with your elimination explanations only leaves one last conclusion, there is a buildup of dirt / corrosion capturing tiny air bubbles which can’t be flushed out. Need to rebuild your caliper. Now knowing the piston has to be a standard size a replacement O-ring / quad ring from another caliper should work. There’s someone out there who knows the answer. Measure the OD and post it as there’s a caliper that size somewhere. Now I will say I have had luck with removing a couple stuck CB750 caliper pistons, cleaned without removing O-ring “DON’T USE SPRAY SOLVENTS”, lubed with brake fluid to reassemble. Time too ride.

"HJ"

[fabiodriven]

I like the sounds of what you're saying Hairy, and I'd be looking into that but I put the bike back together again. I'll have to take it back apart and measure like you said. I really don't know what else to do, lol.

I got the bike all reassembled today and took it up the road. I was filming but honestly there really wasn't that much to see, haha. I got pulled over but the battery on the cam had died at that point. I was doing 60 in a 40. I knew I was speeding. I don't have a speedometer either, it's not a requirement here. I'll probably download a speedo app on my phone and use that in the future. I got pulled over a few years ago doing 40 in a 25 and I felt like I was standing still. The cop today was nice, no ticket.

I'm going to post a short vid, not much to see really. I'm going to record more often and see if I can get something worth filming. The bike ran well today and started every time, but it needs a battery. I still don't know if the no-start issue is sorted or not, but I'm sure I'll be finding out.

https://www.youtube.com/watch?v=prxoymeHNY4&t=83s