Friday, October 18, 2013

MAGNA Mountain Bike / Is this Department Store Mountain Bike Thing Ever Going To End?

Hello and Welcome
As I mentioned in an earlier post, this year will forever be remembered by "yours truly" as The Summer of the Department Store Mountain Bike. This D.S.M.B. belongs to the son of a friend. I was told it needs a new shifter thingy for the front gear thing. (or something to that effect) ltms... I was sure I had a decent set of twist grip type shifters I saved from the LL Bean bike. And after this lad's mum told me this young man had given his other bike to a friend who badly needed one...well how do you say no to that?...... Right! You don't

Above: I hope you are on a Personal Computer or something with a big screen so you can click on this pic and see the labeling that I just recently learned how to do.

Above: The broken shifter is pretty simple, first I locate the replacement. Ok now I disconnect the cable from the front derailleur. I will then remove the short grip by carefully inserting a small slotted screwdriver and give it a quick shot of WD40 inside the grip. Ok the grip is off that was simple enough. Now I pull the shift cable free of any cable guides or braze-ons. For the twist shifter I locate the hole and insert the correct size Allen wrench and loosen the Allen screw or bolt. Now the shifter mechanism will slide right off the handlebars. Now for the sake of keeping it simple I kept the cables and housings with the salvaged twist shifters. So this is basically a remove and replace job. So now it is just a matter of sliding the new shifter into position and tightening it's Allen screw.

Above: Then I route the cable to the front derailleur using the original derailleur cable housings. I make sure the shifter is in the 1 or low position and I have no slack in the cable. And of course I have the chain on the small chain ring and with no cable the derailleur is in position over the small chainring. Now I attach the cable at the anchorpoint and try the shifter. Now it is working fine, so I can install the original short grip this will make it look more original. Remember the thin plastic washer that is probably on the floor goes between the short grip and the shifter. I'll adjust the shifter latter on, right now I have bigger fish to fry.

Above: When I spun the rear wheel it sounded like it was rubbing the frame. It was actually a bad bicycle wheel bearing and badly worn cone shown above. This is kind of cool... The replacement cone and bearing cartridge are both off his mom's bent rear wheel I recently replaced.

Above: On the left is the replacement bearing cartridge. On the right is the bad bearing cartridge. The bad one has been cleaned I suspect the bearings probably turned color as they overheated. The new bearings will be packed with grease before installing. And the axle and cones will get a little grease too. I like a light coat of grease on the axle to protect it from rust.

Above: I do not like the look of this bearing cup, but it feels pretty smooth so I'll use it for now. But I think I will be finding a good salvaged rear wheel and hub for this bike at some point in the future. As I think John mentioned on the face book page recently.... The one good thing about these D.S.M.B.'S is salvaged replacement parts are plentiful. And many of the parts are like new since these bikes are usually disabled so early in their lives. So I guess the message here is, If you can't fix it yourself you better learn fast or buy a better bike.

Above: While I have it off I'll clean up the 6 speed freewhee with a quick spray with White Lightning Clean Streak. And lubricate the free wheel by adding a few drops of oil to the gap and spinning the freewheel in my hand to let the oil work its way into the needle bearings.

Above: Here is the rear hub all back together and working really well. I checked back after a few days and the lad told his mum the bike is working great. I did do a small adjustment to the low (L) limit screw on the front derailleur before I took the bike back and it was working fine. I also had to take a wee bit of tension off the front derailleur cable to get it dialed in.

Above : As for the front hub, it just needed the cones adjusted (they were set a little too tight) and a little grease. The boy should notice this bike rolling 100% better than it was last time he rode it.

Above: The bike ready to go back home. As usual I have placed the worn or broken parts in a zip lock bag. A few other things I did were to reposition the brake levers and reflectors. The chain was lubed with the White Lightning self cleaning lube. And then I just cleaned up the bike a bit with Armor All Cleaning Wipes. Which reminds me I have to pick some up at Meijer's tomorrow.
Now I need to repair my friend Tom's rear wheel. Which ironically has almost the exact same problems. But it's NOT a Department Store Bike. Holeluuija!

Above: Tom's wheel off his Giant Mountain bike. I ran into Tom the other day and He said "Hey Hugh I got something for you". So he opens the trunk of his car and pulls out this rear wheel. Basically he said It needs a broken spoke replaced and could you take a look at the cones, I think they might be bad. I look at the Freewheel and see it is a Shimano (I have the right tool to remove it) Sure Tom no problem.

Above: Yeah these cones are shot alright. So I took the axle, with one of the bearings and the cones and spacers along with the broken spoke to Cycle Therapy in Waterford. I didn't have any black spokes and this is a really nice bike and I wanted tho replace the axle and cones with new. Cycle Therapy had everything I needed. They also had some citrus based Park Tool Chain Cleaning Solvent in stock. This is cool as I have been out of this stuff for what seems like forever.

Above: Although these bearings look o.k. to the naked eye, they have to be damaged if they have been rolling on those cones for a while. The young man who waited on me suggested I reuse the original spacers. I already knew this but I was impressed that he thought to mention it. Ernie has some good people working for him (at Cycle Therapy) who have kept me on the right track more than once.

Above: The take down and reassembly went fine without a hitch. Everything got a good cleaning and re greasing. Did you ever notice it is almost always a spoke on the drive side of the rear wheel that breaks? In this case it didn't matter as the hub had to be broke down anyway.

Above: I have placed the wheel just inside the small shop/garage door so I don`t forget it. I am meeting up with Tom and some other friends in the morning. As usual I have his old axle, cones & bearings along with the spoke in a zip lock bag. I guess I could have tossed the spoke in the wheelie bin. I`m pretty sure Tom knows it could not be repaired ...ltms
P.S. Didn't mention it but I did also true the wheel on the stand, after the hub was rebuilt of course. Chatting with Tom earlier this morning He told me the wheel has 1,500 miles on it. If I understood him correctly the hub was never broken down and cleaned / greased. I guess that would explain the condition of the cones.

Until next time, Please RIDE SAFELY and remember to always.....RESCUE, RESTORE & RECYCLE
Cheers,Hugh

9 comments:

  1. Hugh that was a nice thing you did with his bike -I am sure a deposit has been made to your Karma bank account ;-). The cones on your friends Mt bike have to be the most trashed ones I have ever seen- looks like someone took a hammer to the one in the picture! good call on ditching the old bearings too.

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    1. Hey Ryan,
      lol...I know they are pretty damn bad, they are the worst I have seen as well. Since I posted this I have talked with Tom. (bike owner) And he said that wheel actually has well over two thousand miles on it. I told him if he is riding that much he is going to need to service his hubs. headset and crank on a regular basis.
      Like myself Tom is a former motorcyclist. Wheel bearings on motorcycles seem to last forever. So I totally understand how it didn't occur to him to check them regularly.
      Cheers
      P.S. I saw your last rebuild on face book. Damn fine looking bike! Well done

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    2. Thanks Hugh its on the blog now in if you want am more "in depth" look

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  2. Your a wizard, I like the way you position those cones on top of that lid, looks like it's smiling. I've never seen cones that bad, and I see a lot of junky bikes. What type of oil are you using to lube the freewheels?

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    1. Thanks John,
      Now that you mention it, it does kind of look like a happy face :) For the inner needle bearings I use a multi weight automotive motor oil.(like 5w20 or 10w30) Then wipe off the excess,after I am sure the oil has worked it's way to the bearings. For the outer part (after cleaning with White Lightning Clean Streak) I use a light coat of a "silicone based lubricant" like Tri-Flo or C.R.C.
      Cheers, Hugh

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  3. Ryan is right. That young lad built up his Karma by donating a bike to his friend and it comes back to him with a better than new condition D.S.M.B. Worked up by you. It is a good thing to be part of the bicycle world where we all just try and make things better for people in our lives. Nice work!

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  4. What is the mounted black bar that covers the outside of the rear derailleur? I was helping a friend with his kids department store bike, and noticed one of those on it. Is it to protect the rear derailleur if they put it down on that side? Is it to keep the derailleur from shifting too far and throwing the chain?

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    1. Hey Matteo,
      Yes it is a guard designed to protect the rear derailleur from crashes, drops and trail obstructions. I am glad you brought this up because... The guard can also limit the derailleur if it gets bent inward. So if your derailleur will not shift to the smallest cog and you have a guard like this one. Check the guard before adjusting the limit screw it might be blocking the derailleur. This happened to me once and fortunately I caught it right away.
      Cheers, Hugh

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