Chain Repair

A broken link

Ever since I became confident about my ability to fix punctures on the road (read about it here), I have been thinking about getting a grip over this problem of fixing broken chains as a next DIY thing to learn. A broken chain on a road trip can stop you and force you to walk to the nearest repair shop or home (whichever is nearer). I started watching a lot of chain fixing videos on youtube. What I learnt is this - you either carry a "missing link" in your saddle bag or you learn how to repair a chain for a temporary fix. Even if you carry a missing link, you must know how to break a broken link. I realised that I have a basic tool with me to break and repair a chain in the form of a Crankbrothers Multi Tool 19. So all I need is some practice. Breaking a link is also an important skill to learn. I do not want to do something on the road for the first time. It just does not work. Before starting to drive on my own, I learnt how to replace a flat tyre and put the spare wheel on. I did it several times at home and then one fine day I had to do it on the road and I was pretty much prepared for it. It was the same for puncture too. It has to be the same for chain repair too. I know a broken chain is a very remote kind of possibility. But no harm in learning a new thing. Baba would have approved of it.

This morning, I stopped near a cycle repair shop in Kalighat and bought for myself an old, rusty discarded chain. They charged me a royal Rs 30 for it, which is a good investment to make if one wants to learn how to break and repair a chain. Incidentally, if you are new to the subject - breaking a chain link is an important part of repairing it. 

First was the dirty job of cleaning the old chain. I don't think it has ever been cleaned during its long life, perhaps pulling a cycle rickshaw. I soaked it in kerosene for about four hours - brushed with an old toothbrush and then washed it in detergent water. Nothing much happened except that both the kerosene and the soap water turned opaque black. Finally, I used some IceToolz degreaser and the gunk somewhat went away. 

I managed to learn quite a few things about chain fixing. But before that let me explain a few things. A bicycle chain is a series of male and female links attached by pins - somewhat like a rivet. In the picture above (on the green table cloth) you can see one male with two females attached to either side. The male remains outside and the females remain inside, so to speak.

Usually it is the male part that breaks under stress. When that happens you have half of a broken male link on either end of the snapped chain attached by two pins. You break those two pins which keep the broken bits attached to the females. Now, you have one less male link. You take out the spare "missing link" from your saddle bag and attach it to the two females. It is a relatively easy thing to do. I don't have a missing link. But if I had it, it should not be much of a problem.

In case you don't have a missing link with you there is a way out. It is not a permanent fix but enough to take you home pedalling. On one side you break the male along with a female but you take care not to push the connecting pin entirely out of the link. On the other side just break the broken male part out. So now you have a blank female on one end and a half open male on the other end with the pin attached to one side (see the picture to the left). What you need to do is connect the female with this male, align the holes and the pin in one line and push the half taken out pin in. What I learnt is that the Crankbrothers tool is not capable of doing this last part. At least not on this chain that I was experimenting with. Because the part of the pin that is protruding out is a micron longer than there is space on the tool. This point will not be clear without a video or without you actually trying to do it. To do this one would perhaps need a dedicated chain breaking tool. Even if you carry a chain breaking tool and can do the job, the chain that you get will be one link shorter. There is yet another option. Carry a portion of the chain in your saddle bag and cut out a part of it and put it in your broken chain. But my cycle has the OE chain and I do not have any spare length of chain. Might as well carry a new replacement chain with a link.

I think the easiest thing to do is to carry a few spare missing links. I am yet to buy them but I will. If you are novice and reading this, please remember one thing - these days there are different types of chains with different sizes. You have to know the type of chain you have and carry the missing link that will fit your size of chain. The chain size depends on the gear speed of your cycle. There is a yet different type of chain called half links. They are totally different and used in BMX cycles. They don't have male and female links. 

What all did I learn today ?

Aligning the tool is critical

1. Aligning the chain breaking tool's piston with the pin to break it is critically important. It is not easy to do this precise alignment. It will take some time and practice to do it like an expert. There are two teeth or cogs on the unit (which also double up as spoke tightening wrenches). You have to position the link in such a way that the holes are engaged on the cogs or teeth (if you look at the accompanying picture carefully you can see it). If the alignment is not right nothing will move - certainly not the pin. 

2. Pushing the pin out to break a link is a little tough in the beginning but then a cakewalk. It gets slightly tough again when it is about to move out of the link. If you want to reuse the pin you have to learn where to stop. If you over push it then you are jacked. Don't expect it can be pushed back a little to compensate for your over pushing. It cannot be. Take my word for it.

3. Pushing a hanging pin back in from the other side using the Crankbrothers multi tool is perhaps not possible. Because the pin length (that is sticking out) is more than there is space to accommodate it. At least this experimental chain that I had was too large. I don't know if my real chain on my Merida has smaller linking pins. It's a matter of a few microns perhaps. But in precision engineered products like chain links and Crankbrothers Multi Tool, such microns make a hell of a lot of difference. 

4. If you push a pin even a fraction of a millimetre in, the link will get stiff. It is possible that this happened with me because I was using a very old chain. But I wouldn't take chances with my real chain. 

5. Cleaning a dirty chain off the bike is not easy. Handling the chain itself is quite difficult as it is totally inflexible when it comes to sideways movement. And kerosene does not work too well at all. Using a  good quality degreaser is far better, quick and effective. Unless you have used a degreaser you don't know how bad and useless and dirty and stinky kerosene is. 

Further Learnings on July 3, 2018

After wasting an entire evening watching a boring world cup match between Sweden and Switzerland I decided to destress myself by once again taking up the old chain and see if it is possible to repair the link with my multi-tool. What I learnt is that yes, it is possible. So I stand corrected. The Crankbrothers 19 multitool is quite capable of repairing a chain by half breaking it.

I had, a few days ago, sprayed the old chain liberally with WD 40. Today I half broke a link - pushing the pin just a bit out and then wriggled the male out. After this I rejoined it. It worked more or less smoothly. As shown on youtube channels. Therefore I can do it. Yaaaaaay.

Two things worked in my favour. A little experience. I think last time I had pushed the pin too far out. This time I pushed it a little less. One has to learn from experience by looking at the pushed out pin and decide. Also with liberal WD40 the pin was much smoother to come out and go back in. After the repair the link seemed a little tight. Exactly as shown on youtube. I pulled it back and forth and it became flexible again.

Doing this at home is one thing and doing it on the street, with the chain on the bike is quite another. But at least I have some practice, albeit at home. Something is better than nothing. But one has to remember that this is a temporary, emergency fix. The particular link that is repaired becomes a weak link. The chain must be replaced immediately after the road side emergency is over.

Happy To Get A Puncture !!!

I was actually happy to discover a puncture in the rear wheel of my bike tonight. I accidentally realised it had gone flat while hanging on the stand. I was more than certain it was a flat. I couldn't be more glad by this opportunity to test my newly acquired skill of fixing punctures. After all we don't get punctures to repair every day. So off I went to fix it. I felt so alive to be doing this, when all my friends I know are watching cricket.

Incidentally, this is Wednesday. I had gone cycling on Saturday. Should I be worried about the quality of the OE tubes and replace both of them - front and rear? Probably yes, if I was going on a long tour. But since I stay more or less within the city and carry two tubes, there is no need to panic.

I started the work at 9:35 pm. Finished it at 10:25 without any particular hurry (meaning I could've done it faster). But please take about 15 minutes out of this. Because I had sent Monisha to Nishi to get some lime for marking. She in turn sent Nishi to get it from a paan shop because he had none. All this took some time. So to take the wheel off, tyre off, discover the puncture, repair it, put everything back on, it took me 35 minutes. The first time on road just to change the tube took me more than 40 minutes. Of course at home I was using the floor standing Firefox pump. 

I am still a little iffy with changing the rear tyre, particularly when it comes to putting it back on. I prefer putting the cycle upside down to do this. This time I tried to do it standing straight but failed. I guess once the trainer comes in and I get the training wheel, I will become more adept at it.

This time the puncture happened in a better location, away from the valve stem. I didn't commit the same mistakes of the first time. Marked the area with wet lime. Put the solution thin. Didn't peel off the plastic from top. Used a small patch. Put the tube back on right away and pumped the tyre. Let me see if it lasts. I didn't even test it. 

May 24, 2018

As of this morning, there is no perceptible air pressure loss.

May 27, 2018 

As of this morning also, there is no perceptible air pressure loss. I guess I have reached that stage where you can just repair the puncture and go. But I am still iffy with putting the back wheel on. I have to learn how to get the brake loose a bit. I think the brake pads are too close to the rim in the rear wheel. Need to widen the gap just a bit. I have no clue how that is done. Let me see. 

Fixing a Puncture on the Road

Yesterday the thing I dread most about cycling happened. I got a puncture. Not too far away from home but not a very walk able distance either. I was around 7 kms away from home. Right in front of All India Radio office. It was around quarter to six in the morning when it happened. It was the front tyre.

I will write down chronologically the exact chain of events. But first my mental reaction. "Oh God. Had to happen on a day when I am not carrying my pump. Didn't I just see Rana cross and wave at me near Eden Gardens (he was going towards Mohun Bagan stadium and I was headed towards HSBC)? He usually carries a pump on his back pocket. Let me see if he receives the phone. I have the spare tube in my saddle bag. Or shall I just get a cab and hop in? Feeling like I perhaps need a potty break. Can I wait for that long?"

I first took out my phone and switched off Strava. Next I phoned Rana. He not only received my phone but said most reassuringly, "just wait where you are. I am coming." After about ten minutes he came along. We met near the traffic island in front of the cenotaph where the road forks out towards AIR and Eden Gardens. 

I had half a mind to take a cab and just go home. Rana took the pump out and said, "do you have the tube?" I said yes. He said, change it. Sit comfortably on the side walk of the island and change the tube and then go home. "Oho Rana. Let me just take a cab home." "Dada, you take a cab. No problem. But first change the tube and then take a cab. You will not get another opportunity very soon of doing it on the road. Just do it. Don't avoid it." 

I thought what he says makes eminent sense. Instead of chickening out I should take the battle head on and win it. Once you go through the process next time you will be more confident. The conditions were right. Weather was fine. Hardly any people. India has this problem of onlookers crowding around you when they see you doing something on the road. Most importantly, I would not be completely alone. Rana would be around. 

Rana said he would be cycling around this area and come once every 15 minutes or so to check out on my progress. He was going in rounds along the route of Strand Road - Princep Ghat - Police Training School - Victoria - Fort William - Red Road. Those who are familiar with Calcutta would know this is a circular stretch of about 5/7 kms. 

I parked the bike against a lamp post. Looked at the watch. It was 6:08 am. 

Step one. Take the tools out and keep them ready. I took my tools out of the saddle bag. The spare new tube a Maxxis 700C 18-25 with a 48 mm valve stem, the Park Tool tyre lever set. That's all one needs really. 

Step Two. Take off the wheel. This takes a few seconds. I took off the front wheel. Next was to take the tube out. I had to struggle a bit with the levers. But finally I managed to take the tube out. To my utter surprise I discovered, the tube had still some air left in it and wasn't quite completely flat. I pushed the air out. I had half a mind to try and pump on the same tube and go home. Then I thought, what's the point. When the main work is done, might as well change the old tube. 

I cleaned the inside of the tyre but found nothing. I guess this was a very fine hidden sort of leak. I will have to research this out. The tube lasted for about 650 kms.

Now came the confusing part. The OE tube which had developed a puncture sits snug on the wheel. But this new tube was slightly longer than the OE one. About an inch more. Did I get the right size? I got a tad nervous here and decided to wait for Rana. Soon enough he arrived on the scene. I explained to him the problem. He checked it out and said nothing was wrong with the size. Push it in Dada. "By the way, why did you take off the entire tyre from the wheel?" "Well, I kind of thought this is the right thing to do." OK. Go ahead and put it back. 

Now started the struggle to put the tube round the wheel and fit the tyre back on. I cannot remember exactly what I did but there were lots of trial and errors and finally I succeeded in putting the damn thing back on. One of the tricks to know here is that use both your hands to put the tyre's edge back on so that it is done uniformly on both the sides. 

Next step was pumping the tube up. Rana's small pocket size pump did a wonderful job here. I do not know how much pressure it managed to create but it felt tight pretty soon; the tyre felt tight enough to take me home. After a few quick photographs I put the wheel back on. It had taken a total of 40 minutes to do the complete job. I think next time I can finish it in 20 minutes. I am more than certain.

All photographs taken after the tube was changed

Rana came along once again. I returned his pump with a lot of thanks. He indeed not only saved me, he gave me the courage and encouragement to earn this important right of passage in the world of cycling. My father would have been very proud of me. He always wanted me to learn this very important job of how to fix one's own punctures. But I could never learn it because we did not have youtube in those days. I am sure yesterday he saw me do it from wherever he is. I am very grateful to you for instilling these ambitions in me. Too bad you cannot see it all or I cannot go back home and tell you these stories. 

Lessons Learnt

1. I should have known the tube was bad even before starting. I found it was almost flat in the morning when I started. Tubes lose some air when you don't ride for some time. But they don't go flat like that. Alarm should have rung when I found the back wheel did not lose that much pressure. 

2. Always carry all your equipment. Pump, spare tube and levers. I was lucky I had Rana. I might not have him. I normally carry my small pump. But these days since I am riding mostly within city limits I got a little casual. But I have to remember that walking seven kilometers with a flat tyre bike is not easy or comfortable.

3. Should have perhaps checked out the new tube (Maxxis bought from Good Earth) in the comfort of my house rather than on the road. I have already ordered for the next tube. A Schwalbe 700 18-28C with 60 mm valve (my OE needs 48 but this brand does not seem to have that size. 40 or 60 - I chose 60). 

4. Don't be afraid of soiling your hands but you can use the gloves to take the wheel out. Also, overcome the inhibition to squat on the footpath. After completing the job, I used the water from my drinking bottle to wash my hands.

5. Have to practice taking off the rear wheel. It is not as easy as the front wheel. Particularly putting it back on. I have done it a few times. But it's like those tougher chapters in Mathematics. You do it once and then avoid, thinking you will somehow manage in the exam hall. In the exam hall a friend my bail you out but on the street there will be no one to help you.

6. Must carry small change for Sulav Souchalaya and some toilet paper in the saddle bag.

Epilogue

As I was riding back home slowly down the road near Victoria and it had gotten a bit late by my standard (around 7ish) I saw a group of amateur photographers out on their morning shooting practice. The probably spotted me before I did and started clicking me in all seriousness. I guess with my red bicycle and orange jersey I was perhaps looking like a professional cyclist to them (but a complete MAMIL to myself). I smiled at them. That possibly spoilt their frame but I surely felt like winning a stage in le Tour de France.

Back Home

Just checked the punctured tube. A. The core of the valve is possibly a fixed one and cannot be removed to apply Loctite (incidentally it is available in India now through Henkel). B. The pressure in the tube that I fixed on the road was just 20 psi. Disappointingly low and could cause another puncture if I had hit a hole in high speed. But as I said, it felt pretty tight to finger pressure. I have to check how good my own pump is. C. The air loss problem is not with the valve. There indeed is a leak that has developed just under the valve area. I filled the tube with a lot of air and sunk it in water. Bubbles immediately started coming out from a point. Possibly in low pressure the air loss isn't much. But nevertheless it is not insignificant. I am tempted to buy a puncture repair kit and fix it myself to keep it as a spare tube.

Fixing The Puncture

Certain things about Calcutta are so disgusting. After discovering the small puncture in the OE tube I was in a dilemma. Whether to fix it myself or get it done by one of the street side repair guys. I thought DIY would mean investing in a few patches, some cement and a piece of sandpaper (these repair guys typically paste the sandpaper around a small metal tube and make a nice sanding block that is useful). I have no problem with the investment but since I don't foresee too many punctures happening in the future I thought investing in the full kit would be a waste of money. Also the cement might freeze by the time the next puncture develops.

So last evening I went to the nearest puncture repair guy in the neighbourhood. This is a small shop near the Mudiali Meat Shop and they repair motorcycle, car and commercial vehicle tyres and tubes. I went with the OE tube and my mini pump because I foresaw them saying, "we don't have the adapter to pump this valve" etc. This bored looking Bihari shop owner (who didn't have any customer) took a casual look at the tube and said, "no we cannot do this" and looked the other way. I told him that I had the pump but he refused to listen, saying this is too small for them. He refused to get into any discussion and kept saying, "go to a cycle repair shop".

There is a second shop right next to the guy. This fellow didn't look as bored but he also denied. I asked him what is wrong and why is a cycle tube so different from a car tube. He said, this type of rubber is too thin and we don't have the right file to clean it. Our files would tear the rubber. Go to the cycle repair guys. They will do it with a sand paper !!!

Today I went to the nearest cycle repair shop. This is just before Grand Saloon. The bugger is closed.  It was in the evening. Around 7.30 pm. He is not even a shop. Just sits by the road side with a floor standing pump and a wooden box with some tools. But I see him busy fixing a bike almost all the time.

Adamant. I went all the way to Kalighat Road (the friendly neighbourhood red light district) where there is a big cycle repair shop. It's a proper shop with 2/3 mechanics. This bugger is also closed. Had to come back home fuming.

However, I learnt to push out the last mili gram of air out of the tube. You just roll it up like a tooth paste tube, working towards the valve and keep pressing the valve from time to time. Every single drop (?) of air would come out and the tube would become completely flat.