[Torq-D]

Hats off to u @that_sedate_guy for such a beautiful thread. Recently, I bought back my R15 from the same guy whom I had sold to, in 2011. Mine is MY 2008. Before joining ship, I had given my bike to yamaha dealer for all cosmetic repairs/replacement. I bought it back just because of remorse I have had after selling it.

I didn't ride my bike after buying since its RC was expired and also due to lack of time, so don’t know the exact condition of engine and it’s ancillaries. So your thread happened to me at right time.The attention to detail which you have worked with on the bike is something which only a highly passionate/experienced and mechanically sound person can do.

Now, I have someone to look upto when I take up my bike’s engine overhaul after I sign off from ship.Thanks a lot mate!

[that_sedate_guy]

Originally Posted by Torq-D

Hats off to u @that_sedate_guy for such a beautiful thread

Thanks a lot for the support, mate! I can understand the feeling of letting a vehicle go and then feeling bad, almost like ghosting an actual person or something. I had a Pulsar 150 during my work tenure in Uttarakhand which I had to sell off when I moved back to Tamilnadu because I didn't have the time nor the money to go around re-registering it at that time. In hindsight, I could've simply brought it here because absolutely no one questions the registration nowadays and I seriously, I mean seriously loved that bike.
I'm glad my journey of the rebuild could be of some help or reference to you. I'm also not going to shy away from posting mistakes I've made because this is really not a perfect build no matter how much care I've tried to put in.
If at all you decide to do a full overhaul of your motorcycle, one word of my advice would be to please be sure never to lose even a single screw or nut in the process. Even if a part is damaged fully, retain it until you get a replacement. Also, either go for a really good mechanic or be prepared to spend weeks and weeks on it if you plan on a DIY. Keep us posted on your journey too! As for me, stay tuned for the next part is going to come up really soon.

[that_sedate_guy]

Ladies and gents, were back in business with chapter three!

Starting with the crankcase gears, here’s where a bit of know-how is required because until this point, the assembly is quite straightforward. I had quite a large bunch of parts to put together and I wanted to do all of it in one go because the parts were all stored in oil and now that they were taken out, they had to be kept with the oily film intact and kept free from dust and dirt. This meant that I had to close up the crankcase as quickly as possible. You might notice the balancer shaft in this picture because this is an older photo and I forgot to take pictures of just the outer gears.



The very first assembly to go in was the oil pump because this sat at the farthest side. The pump in itself was a quick bolt-on job but the original screws were completely bulged out and I had to get new ones (M5 X 25), applied some Anabond thread locker and fitted the pump. The splash plate was next which was also fixed in place by two thread locked screws.

Simultaneously, I also took care of the gear selector fork assembly and fixed the spring in place. A word of caution when working with springs is to always load springs with tools and not with bare hands. Also, never sit close to loaded but not seated springs when trying to wedge them in. Always stay out of the direct ricochet path of the spring. Even if it were to bounce back and hit you after the first hit, it would not end up in an injury because the energy would already have been dissipated to acceptable levels.

Right next was where some care was required. I’ll take you through a boring theory class of that now.

The engine converts the high impact energy of a reciprocating mass into rotary kinetic energy and this kinetic energy is in-turn, generated at the piston only at one stroke which means that the engine needs momentum to carry on through the remaining three strokes. Now, when the engine is engaged to the gears, the vehicle’s momentum takes care of keeping the engine alive (the reason why engines stall when in gear and too low a speed). But when the engine is idling, internal masses need to be put in to provide a counter-mass and keep the crank rotating. This is taken care of by the crank flywheel which stores surplus energy and releases it when the engine doesn’t develop power.

Even though the crank is a rotating mass, it is an unbalanced rotating mass and hence leads to vibrations when it rotates. Coupled with the reciprocating mass of the piston and the oscillating mass of the connecting rod, the engine produces a lot of vibrations which is a key disadvantage of single cylinder vehicles. To reduce this inherent unpleasantness, one of the many solutions is to have an intentionally equal and opposite unbalanced mass relative to the crank affixed to a shaft. This is called the counterweight or the counter-mass and is directly coupled to each other by gears. This shaft is called the balancer or the balancer shaft. These elements combined lead to the smoothness we all relate to well-made-machines.

With this short knowledge snippet, let’s get back on track. To keep the unbalanced mass rotating exactly opposite to the crank mass, the balancer shaft needs to be gear driven in the opposite direction in the same speed ratio. These gears were the first to go in.



The gears have a simple but effective PokaYoke (Japanese term for fool-proofing) system. The gears are orientation-locked to the respective shafts by woodruff keys and are in-turn orientation-locked to each other by identification marks on both the gears which are meant to be aligned upon assembly.

This is a very important step. Minor errors like misalignment by a tooth or two between the gears will create issues like excessive noise, uncontrolled resonant vibrations and can even lead to bearing failure although such chances are rare because the vibrations will be quite pronounced.

Missing the alignment by more than two gear teeth will lead to very heavy vibrations that will render the motorcycle unusable.

Warning: It is also possible to assemble the balancer shaft at a larger angular mismatch but such large angles will not cause vibrations because at the very first crank, the balancer mass will wedge itself against the crank, damaging almost the entire crankshaft and balancer shaft system, including the gears and the bearings. The engine will behave as if it has completely seized up and repairing it will be an extremely time-consuming, difficult and costly affair. Please exercise extra caution in this step should anyone attempt this.
Here, you can see how these markings are to be aligned. In this condition, the crank mass and the balancer mass cancel each other out as intended by the design of the engine.



These gears were then locked by a nut & washer combination and torqued up. To prevent the nut from loosening, the end washer was of a sacrificial bend washer type which was bent towards the hexagonal profile of the nut.



With the balancer gears in place, the clutch assembly was up next. However, I was yet to get a set of new clutch plates so I simply assembled the clutch housing and let it be for the time being.



Following this, I shifted my focus to the other side where the Magneto would reside. I slipped the timing chain first and placed it on the crankshaft sprocket.



The timing chain was then tied with a copper wire and then pulled taut and kept in place to avoid slipping from the sprocket when the flywheel was being mounted.



With the chain in position, assembly of the starter gear, the flywheel with the needle roller bearings, the washers, the half-moon shaft key and the outer washer was done and locked with the magneto lock nut. Here's how they all looked just before going in together.



After that, I affixed both the crankcase covers temporarily with just a couple of screws and started to work on the cylinder block.



I made short work of the lower cylinder gasket and the block.



The piston rings were put in with care to ensure that the ring openings did not match up too much, the keyword being, “too much”. Tutorials and rebuild walkthroughs always swear by arranging the piston rings in very specific angles. However, there are two points to consider

1. Piston rings DO NOT have such wide openings when they are assembled inside the cylinder. Piston rings might not look like too much work but they are also precision made components that are designed to slide in the piston groove and exert a sealing force on the cylinder walls while also ensuring that the end gaps are almost fully closed.
2. Further, piston rings are not stationary elements. Try all you might and assemble the rings with arc-second precision and the rings will rotate in the grooves at the very first crank. This means that within half a crank, any angle that has been set will start varying.
3. In addition to the above point, the rings move at different angular rates. This means that the angular position of each ring with respect to the other does NOT remain constant. Thus the ring openings will meet at different intervals or may not meet at all which cannot be ensured whatsoever.

Hence, I personally would not fret too much about ring orientation. However, it does do good to ensure the angles for the first time during a rebuild because it helps with building a good amount of compression until the oil starts circulating.

In the meantime, I gave the cylinder head to the guys at M.A Auto whom I mentioned before and they did the lapping and setting for me. I fitted up the cam follower arms after a thorough cleaning followed by the camshaft and setup the valve stem clearances as well.





With the cylinder head ready to be put back, I did think of using my homemade tool for putting back the valves after getting them lapped and set. However, the guys at the shop offered to do the entire assembly without extra cost so I decided to spend that half hour with making yet another special tool which I’ll detail below.

Firstly, here’s a picture of the valve tool I made in two minutes from a stainless steel curtain rod.



Now, on to the other tool I was talking about. With the other gears in place, the clutch had to be assembled. I had previously assembled the clutch housing but did not torque it with the wrench. To do that, I was in need of something to rigidly hold the housing in place while I torqued the housing nut. YouTube referrals gave me the idea of using the discarded pressure plates as perfectly meshing holders. I took one such plate and welded it to two rebar pieces using my light duty arc welder. I had to grind and rough up the plate surface and also turn the current up quite a bit to get the weld to stick but soon enough, the tool was ready for duty.



Using this special tool, I locked the clutch housing and tightened it to the full torque. Now, I do not possess a torque wrench and with good ones being eye-wateringly expensive, I simply tightened the fasteners by hand feel. While there was a possibility of a slight overshoot of torque, my past experience in the Machine Assembly factory rewarded me handsomely in terms of torqueing techniques.





Now that the clutch housing was in place, the clutch plates were finally bought and assembled like a nice inedible burger with this arrangement:

Inner friction plate – Pressure plate 1 – Friction plate 1 – Pressure plate 2 – Friction plate 2 – Pressure plate 3 – Outer friction plate

Unfortunately I did not record the clutch assembly since I was so engrossed with setting the clutch actuator. The actuator rod went in first, followed by the load transfer ball and finally on to the actuator nut. One might wonder about the function of the ball. It serves as a ball and socket joint between the trans-rotational clutch shaft and the clutch actuator nut which moves only forward and back. On top of this goes the outer clutch housing held in place by the four clutch springs and torqued with their respective hexagonal screws.

Clutch setting: This is an important step during a rebuild or a clutch job. The clutch plates need to separate and free up when actuated and engage together when the clutch is not in operation. The distance adjustment of the clutch actuator takes care of this but this has to be done properly otherwise, the clutch actuator mechanism can either break or the clutch will never work properly. To avoid both sides of this unpleasant spectrum, the actuator nut needs to be set to the freest setting and assembled with the housing. The threaded rod of the actuator nut then needs to be tightened just enough to let the nut touch gently but firmly on the outer clutch housing. That’s it! Lock the threaded rod in place with the locknut on the outside and you’re done with a properly set clutch.

Caution: Be very mindful never to overtighten the threaded rod past the butt point because one, it will damage the threads and small auxiliary engine parts can be a pain to source. Two, your clutch will end up in an always half-engaged position. This can:

1. Rapidly wear off the new friction plates and leave you wondering why the new clutch went to heaven in a week.
2. Overheat your engine to ridiculous amounts
3. Burn your engine oil and cause nasty deposits, crankcase debris and the like.

Once the clutch was assembled, the crankcase covers were put back but the screws still could not be tightened fully because there were a few screws missing from the previous time the engine was rebuilt. Until I made time to go out and sourced the screws, I temporarily fastened the crankcase covers and moved on to one of the most irritating parts of the build, the timing adjustment.

Within moments, the cylinder head was mounted on the cylinder block and the engine block screws were installed. However, the fly in the ointment was making sure the timing chain did not slip out of the crankshaft. I ensured this by tying the chain to the outer part of the engine with a copper wire and set about tightening the cylinder head but not to the full torque spec because I did not want to wrestle the bolts in case I messed up the timing adjustments and had to open it back up.



Now, the actual driving components were all put in shape but the most important part of what makes an IC engine and engine and not a catastrophe is the timing system which I’m detailing down in writing as we speak here. Hope to get that bit out as well in the next part.

Until next time, stay curious, stay learned!

[DocOn2Wheels]

What better utilisation of time I could have had other than going through this entire thread while my mother's never ending festive shopping was on the go. First of all I would like to thank you for your posts on my thread, they really did help me a lot in my journey! In one of the posts you had mentioned about you yourself working on a friend's bike. I was curious whether there's a thread, and here I am
I look up to you!
Waiting eagerly for the update.

[that_sedate_guy]

On to part 4 we ride!
Next came the annoying part of putting in the timing pulley and adjusting it. To start off, I had to set the engine to the top dead centre (TDC) this was done by rotating the crank with the torque wrench until the notch in the flywheel aligned with the notch on the crank alignment window. The notch was barely visible but I got a hold of it and aligned it.



I removed the copper wire carefully and inserted the pulley and was making good progress when I couldn’t open up the chain past a certain point and push the pulley in.



I found out that the slack adjuster was pushing against the chain and fixed that in place with a screwdriver and more copper wire and attempted the pulley again when my knee hit the screwdriver holding the adjuster and the chain tightened down again and slipped from my fingers falling into the darned abyss.

“Okay, it’s fine. We’re fine. Even experts struggle here,” I said to myself and with a heavy heart, opened the cylinder head again and pulled the chain out only to see that it had come off the crankshaft sprocket.

I let out a heartbreak laugh (no, not a heartfelt one) and spent the next ten minutes trying to battle the chain back into the sprocket and goodness me, it was NOT easy! The worst part was that I had to take off the magneto cover to set the timing chain in the crankshaft sprocket. While the cover was out, I remembered to mark the crank notch much clearer with a marker pen. Something good out of adversity, I guess. I finally managed to get it in position and tying it again with the copper wire, I assembled the cylinder head, taking care not to torque the bolts in case, I had to redo this entire step. I succeeded this time with the timing pulley though by learning from my previous mistake and taking care to lock the slack adjuster for good.

Inching the chain forward notch by notch, I brought the timing pulley in the proper position where there is a specific notch on the pulley which needs to align with a mark on the cylinder head.



With the pulley aligned and pushed into the camshaft, I realized I couldn’t put the decompression pin in that easily and had to take out the pulley a little bit. Being a very smart person, I pulled the pulley without taking out the decompression pin and the pin fell into the chamber. I nearly got a full bout of diarrhoea seeing the pin clank its way down in the dark mechanical pit.

“NONONONONO!” I exclaimed in exasperation and desperately tried to think of a quick remedy. I locked the pulley with the locking bolt, lifted the entire engine in my hands and tilted it upside down in hopes of shaking the pin out because I seriously did not want to open up the entire engine for one small pin. I felt so stupid for making such a rookie mistake but then again, who doesn’t! My panic shake miraculously worked and the pin came out in a few tries almost exactly like when I used to drop my striker inside my guitar and shook it out. I took extra care in the next attempt and successfully installed the pin without dropping anything else inside. A little less strength in my hands would have forced me to disassemble the engine again to retrieve the tiny pin, phew!
The critical part of the build was now water under the bridge. You probably remember me stating that the crankcase covers had a couple of screws missing. Along with that, the burnt oil was also not cleaned up since I knew that those covers would be going back in the last. Now that all the other work was done, I set about cleaning the clutch side and the magneto side covers.



The armature was completely covered in burnt slimy oil and had to be cleaned off first.





The armature cover looked extremely dirty but a couple of minutes in, I realized that the apparent dirt was due to the horrible surface finish on the interior of the cover. It was understandable however, that the inside of the covers were neither a performance part nor an aesthetic one.



After blow drying the armature cover, the coil was assembled and the screws were fixed in with thread locking compound.



I then spent a quick few minutes cleaning up the valve cover and putting it back on with a new o-ring.



Next were the peripherals. The fuel sensor was the first to go in after a thorough cleaning and drying cycle. It was surprising to see the amount of greasy dirt accumulated on a part that was supposedly oil free.



The non-return valve for the coolant was next. Cleaning it up was quite a challenge but it was nothing to write home about.



It was all sunshine and roses until I fixed the valve and valve housing in the cylinder head. Exactly at the very last turn of the bolt, the housing developed a crack which was not making me happy. If there was a name for decayed metal, this bike would be it, sigh. I simply set it aside for the time being and moved on to the next part.

The radiator was in bad shape and it was completely blocked in a lot of places by dirt. Some of the fins were badly damaged due to stones hitting the front part of the fins.



Using a knife, I straightened up most of the bent fins and then sent it outside to a known mech who checked the radiator for leaks, dissolved all the sludge with solvents and then cleaned it up completely.



The radiator was sort of a small detour from the engine build but although it had to be done sooner or later. Moving on, the next in line was just assembling all the covers which were already cleaned up. The magneto cover was quickly screwed in place followed by the clutch side cover. The clutch cover had one extra step, though. The clutch shaft is an oil pumped shaft. Hence, to ensure proper flow of oil, there is an oil seal which gets fitted in the housing.



The seal fitment is straightforward with just a simple press fit but the rubber needs to be liberally lubricated beforehand. Please do not skip this step since lack of lubrication can actually rip apart the rubber lip of the seal. Also, fitting the seal is best done with soft materials used as an interface between the striking tool and the seal. I like to use a piece of soft wood over the seal.



Finally all the covers were put in place and tightened with the wrench and some of the dirty external surfaces were given another clean with diesel and then wiped dry.



The major part of the work involved in rebuilding this bike which was the engine was complete. However I could not sit still on the fact that the frame and the overall bike was in such an abused state that it just did not make sense to leave all of that untouched and only focus on the engine so I decided to do something which was never a part of the plan in the first place which was to do a full-blown restoration of the entire motorcycle.



You can probably see where this is going. Yes, what started out as a simple trip to the mechanic, blew up into a complete engine rebuild and just when it was all closing off, the ugly truth about the rest of the motorcycle reared its head and the entire project took a detour and morphed into a full motorcycle rebuild.
I am however, signing off on this part of the build here to ensure that the engine part gets a proper closure and the frame gets a designated start point. That, and the fact that I haven’t compiled it yet!
Hopefully, I’ll be able to get a hold of the next issue pretty soon and will keep you guys drunk on grease-monkey content. See you all soon and until then, happy motoring!

[vaibhavyagnik]

Wouldn't it be wise to get the engine started first, check if its ok and then proceed for a full rebuild?

[that_sedate_guy]

Originally Posted by vaibhavyagnik

Wouldn't it be wise to get the engine started first, check if its ok and then proceed for a full rebuild?

That does make sense. However, the reason I'm doing the chassis build to completion is because the frame needs to be intact with the wiring system, the air induction system and the fuel system in order for the engine to be started. Granted, it can be done offline with starter sprays and the ecu, airbox and throttle body all hooked up but while I did consider going that way, it just did not seem any less complicated than getting everything assembled on the frame itself. If at all a problem presents itself, the engine is only three bolts away from getting disassembled rather than have a bunch of different systems all working but not fixed in place.

[that_sedate_guy]

Part 5 - Out of the frying pan and into the fire!

I parked the motorcycle in the garage and took a full assessment of the frame, the fairings and all the peripheral parts. There was an extra fairing that had been fabricated to cover a portion of the headlamps and make the face more aggressive. That however made the motorcycle look a tad bit smaller and hence it was to be deleted from the final look.

Most, if not all the fairings were scuffed here and there, with some deep gouges on some of the parts. The paint was fairly intact but because of the scratched and damaged areas, the paint had to be taken off fully. Further, a lot of the parts were grey in colour, including the fuel tank. This did not sit well with me since the RTO documents were specifying white. Hence, I decided that the entire motorcycle would be painted in pure white and then stickered red.

It was thus clear that the motorcycle needed full repainting. But before that could be done, there were a lot of other parts which needed attention.

First things first, with the condition the motorcycle engine was in it was only logical to look at the fuel system. I disassembled the fuel tank and my doubts were well placed. The filter on the fuel pump which was inside the fuel tank was completely blocked up and was supposed to be white but was dark brown in colour. Well, that was something to clean for another day.





Moving on, I remembered that the radiator had quite a lot of stones and other damage on the metal surface. This meant that there was a high possibility of those same stones attacking the front suspension, frame etc. So to clear my doubts, I started stripping down the entire frame. The handlebars and the switchgear came off after which I set about disassembling the triple clamp.





Removal of the triple clamp meant that I had to take the wheels off first. The front wheel put up quite a bit of a fight before the bolt came loose. It had to do with the fact that the bike was constantly ridden in less-than-ideal conditions for prolonged periods of time. Once the front wheel was off, the shock absorbers were taken out, finally giving access to the triple clamp which was promptly disassembled.



The shock absorber housings were fine however, the rods inside had a lot of deep scoring marks and deep wear marks at specific regions. It was a sign of bent rods that had to be replaced. The replacements were very expensive so we got a set of forks from a second-hand market in manageable quality to run by until budget permitted for a fresh set of forks. The housings were not compatible however and hence, we swapped the rods alone for which we had an insanely hard time getting them fixed because no shop had the tools for the R15 fork rods. Many garages and mechanics later, the rods were fixed, fresh oil was filled and the housings were cleaned up.

Disassembly timelapse

The housings had a black coating which was flaking off in most places so I used a strong paint remover to strip off all the paint and grime off the housings and scrubbed them well with steel wool. They were then wiped off dry before being cleaned again thoroughly with paint thinner. After that, I masked the seal and rod areas with tape and spray coated the fork housings with metallic gold paint. I changed the colour to make it complement the new paint scheme I had in mind.



Upon removal of the triple clamp, it was clear that the vehicle had been in at least one crash. The cone set was completely damaged, the bearing race was cracked and all the bearing balls were crushed and were mangled out of shape. It might not be possible to see the damage through the image here but some of the hardened steel balls were even showing signs of stress fractures!



The front end of the motorcycle was either dropped into potholes left and right without a care in the world or the bike had met with an accident. Either way, there was no option other than replacing the entire set.



I took a note of this catastrophe and then proceeded to gut the motorcycle down further. I removed the head lamp assembly and then proceeded to take out the wiring harness.





Since the wire ties were quite old, it was easy to take of the harness. As scary as removing the wires was, I knew that it had to be done because I could not afford to keep all the expensive electronics in the frame while working on cleaning the frame, taking care of the rusted areas etc.



To save myself the trouble of looking up complicated wiring diagrams during reassembly, I took pictures of confusing wire connections.



This is what the guts of a motorcycle looks when it's all laid out on the floor.



Mr P joined me at this point and we set out to work on removing the accessory holders and the key electrical component holder.



Then we went to head to remove the foot rests, rear mudguard and finally the entire swingarm.



Once the disassembly was done, I quickly set about cleaning the cone set bearing. The balls were damaged and the bearing races had severe dent marks. The bottom bearing race could not be saved but that was not a cause for concern because the entire thing had to be replaced anyway. I simply cleaned the ball cages since the cages were not part of a cone set even if I were to purchase a new one.



The triple clamp stem was then cleaned with diesel to remove all the old grease which had solidified into a thick mess. The parts were then wiped and set aside.

Triple clamp cleaning

Meanwhile, I realised that the crank access cap was too damaged to be used again and this particular part proved extremely difficult to source because not one shop had it available. We ended up getting it from an old parts dealer but regardless, it was a huge in convenience.



Then we turned our attention to the front brake caliper. The pistons were seized and were locked in too tight to be pulled out by caliper pliers. I followed a trick from a YouTube video, putting in small wrench sockets into the piston and using the Allen key to turn the piston and take it out. Even with such high leverage with the Allen key, it was extremely difficult to take the piston out because the seals were completely damaged.

Piston caliper removal

The dust seals in the caliper were eroded by salt water which was to be expected considering that the bike was written in Chennai there by increasing the possibility of exposure to seaside air.









Even after removing the seals, the insides of the caliper were full of oil mixed with dirt and pieces of rubber.

The rear caliper was in exactly the same state so after taking that piston out as well, I replaced the piston seals. The rear caliper dust seal on the other hand were equal if not worse in terms of availability to the crank access cover. However, since the old one was not actually damaged or eroded, I just made do with the old seal.



With the calipers set, I took apart the rear master cylinder bit by bit. I did not bother with servicing the front because it was in good condition and there were no leaks either.



Every part was rusted, everything was seized and the smaller parts simply disintegrated during disassembly.



The split pins on the smaller studs became powder when pulling out and had to be poked out. I made a split pin out of high temper steel wire to replace it.



The parts were all cleaned with diesel, sanded and dried.



It’s quite amazing to see how many parts actually go into a motorcycle. Here, what we have laid out is just the rear master cylinder assembly and yet, so many parts come together to make it work.



And all those parts assembled back up, give us a clean, serviced rear master cylinder.



With most of the mechanical issues all sorted out, it was time to look at the cosmetic aspect of things. Like I mentioned above, the entire motorcycle was in need of a paintjob and I had already come too far into the build to just skip on aesthetics so I thought I might as well go all in. I arranged all the fairings and other parts to be painted in a line to get a sense of the volume I would be needing and did the calculations AKA eyeballing. With a rough estimate in mind, I went ahead and placed an order for the spray paints online. Meanwhile I also bought scrubbers and paint stripping liquid to remove the old paint.

With everything taken out this was how the motorcycle looked. Agreed, it looked like a complete disaster but this was just the start of taking care of it all.



Until the paint arrived it was just waiting and prepping time. All that and the painting process will be up in the next part. Stay tuned, everyone! Until next time.