The problem with sports bikes.

A sports bike, in my opinion, is one of the most exhilarating bike type/layouts available on the market. There’s just something about these full fairing beauties that makes you feel like a MotoGP rider as you fly down the straights and try to drag a knee around bends. A sensation I’d assume to be similar to straddling a stinger missile. Apart from just being fast, these machines look fast even when standing still. Poised like a predator, just waiting to pounce.

However, those beautiful body lines on that aerodynamic masterpiece of a fairing kit often hide some serious flaws. Failures, leaks and breaks are often hidden behind some sort of panel, cover or fairing. Something that I have recently discovered on a bike of my own. For quite some time I’ve noticed that my chain had been gathering a lot of oil residue. Something I wrote off to the cheap chain lubricant that I have been using. After a recent trip to Hartebeespoort dam, I discovered that the oil seal on the gearbox output shaft had finally given in. It had been slowly leaking and mucked up my chain. The long trip must have pushed it beyond its limits.

Little old me decided to pull the seal in the easiest/crudest way possible and went to all my local part stores to find a replacement. Turns out it’s a part only Honda brings into the country, and to my delight (sarcasm) it was on permanent back order. As my only resort I had to order this, along with new final drive dampers, a sprocket set and chain. The parts, apart from the seal, were in need of some attention and what better time than down time to do some maintenance. The order had been placed three weeks ago.

This brings us to the day before yesterday. I decided to check on the progress of my order. Luckily, my parts (some all the way from Japan) arrived mere hours before I decided to check on my order.

As soon as I arrived home I set about fitting the new bits to my bike. Not really in the mood for manual labour, I started with the rear drive hub.


Fresh dampers going into the rear drive hub.

I’ve been experiencing tons of shudder from the rear wheel on pull away and under engine braking. Coupled with a lot of play in the hub when the bike’s in gear, leads to the obvious conclusion that the final drive dampers are shot.

Upon disassembly, I discovered that the original rear dampers had turned to dust, literally. This meant dusting out the rear hub and installing the new dampers. Easy as pie, right? Here’s the interesting thing regarding the NC24-100’s damper set up. The forward and rear sections of a single damper is joined in the casting/moulding process. To those of us who aren’t in the know, one has to remove this joining section in order to assemble the hub again.


New, generic sprocket vs old, lightweight sprocket.

Part of my rear drive hub maintenance was to fit a new rear sprocket before fitting it back on my bike. I had opted for a cheaper, aftermarket/generic sprocket as this was the best option for my budget. I use the term generic loosely, as the sprocket only fits a hand full of bikes, at most.

I would have preferred to replace the “lightweight” sprocket with one of the same type and make. Not really for any specific reason apart from the fact that I prefer the way it looks on the bike vs the generic one. I don’t quite understand why the “lightweight” sprocket costs that much more, as there is barely any difference in weight between the two sprockets.


Rear drive hub complete.

As I’ve said before, I don’t really like the way the new sprocket looks, but function over form. The old sprocket had been worn down very badly, and has served me well for a few thousand kilometres. It was time for it to be replaced.

The new sprocket is a tad heavier, and this makes me curious to see how it affects the ride, if it will at all. I really don’t see it having any noticeable effect for a bloke using the bike as a commuter and weekend get away.


Place oil seal here.

Everything I’ve described up to this point has absolutely nothing to do with the title of this post. The reason I feel this post is aptly titled is the instructions I received from the technicians on how to install the pesky little oil seal. It turns out that the oil seal has a lip that fits into a small groove in the upper crank casing. The easiest way to install it is to split the casing and insert it. Bugger…. …. ….

See here’s the punch line. In order to split the crank casing an a V 4 engine, one must remove the exhaust manifold that acts like a cradle around the bottom half of the engine. Take into account than on the NC 24 frame, the rear section of the manifold is blocked by a section of the frame. Therefore those bolts cannot be undone. Therefore the entire engine has to be removed in order to gain access to these bolts. I repeat… Bugger … …


Motor down.

This brings us to yesterday. A day I would spend on nothing else, apart from removing the V 4 power plant from my beloved bike. This job is hard enough with two people. Think about how bad it was if you were man alone on this job.


After about two or three hours of draining fluids, undoing cables, wires, hoses, radiator mounts, and oil coolers, the engine found its way onto the floor of the shared garage. Here’s the fun part. After that massive hunk of steel and aluminium hit the ground it was time to wrestle… A good 120 kg (approximately 264 lb) dead lift brought this little power plant to rest on top of my newly claimed workshop table.


On the table and starting to open up.

Now the fun could begin. Although I’ve owned this bike for about three years now, I’ve never had reason to open up the engine apart from the superficial. When I was restoring the bike, a quick glance into the casings with the sump removed revealed a nearly immaculate engine.

I set about removing the side covers over the magneto/stater and the opposite end which covers the clutch drum assembly. The starter, water and oil pump, and sump also had to go, as they were blocking access to some of the bolts holding the casing in place. Lots of care must be taken in removing the stater, any damage could lead to some catastrophic consequences.

Another big risk is, removing the lower casing leaves the crank shaft unsecured. Any movement or slippage on the cam gear train could have monumental consequences. Therefore it was time to call in the assistance of our in-house mad mechanic, Mechanical MacGyver. Not only has he had experience with similar jobs on other engines, he’s also been working on engines since before I was even born. This is a walk in the park for our mechanical maestro.


DANGER!! Crank unsecured.

Minutes later, the crank case was open and the gloop left by the former mechanic had been scraped off. This is the point in time where I start sweating bullets. I was unable to get hold of a shop manual for the NC 24, and therefore I would be unable to reset the timing marks in the event that something does go wrong.

And I do believe that nothing was nudged or moved in any way. The slight markings I had made on the cam gear train teeth seemed to be unaltered. However the only way I would truly know if everything is fine is to take this little monster out on the road again.


The troublesome seal, finally in its resting place.

Mechanical MacGyver made short work of the seal installation and the crank casing was sealed with fresh sealant and tightened down again within an hour of it being opened up in the first place. During this time I was able to get a glance of my main crank bearings, which seemed to be in amazing condition for a bike that had been badly neglected before I purchased it.

With the crank casing finally tightened down, and the oil pump and tubing securely back in place, we called it a night. My grandmother used to say that night-time work is shady work (an Afrikaans saying that seems to lose a lot of effect in translation). Keeping with that saying I will try to complete assembly of the V 4 power plant during the course of the day today.

It’s been more than three weeks since I’ve been able to go for a ride, and this has driven me to the edge of insanity. Once one has grown accustomed to biking everywhere, being trapped in a cage and stuck in traffic makes one long for the freedom offered by an iron steed.

For those of you who are on the road, I wish you a safe ride, and enjoy the journey.



3 thoughts on “The problem with sports bikes.

  1. Pingback: 2017 Bucket list kicking the bucket. | The Bike Addict

  2. Pingback: The road restarts | The Bike Addict

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