Thursday, June 18, 2015

The best laid plans of mice and idiots on motorcycles.

Well, we had it all figured out, the four of us finally going to the Black Forest. But then one of us couldn't make it because of work so we decided for Abruzzo again.
And now another one of us has had an accident and is actually going under the knife today, which means no riding for a little while.

So, the trip is off, perhaps we'll go towards the end of August but I won't bother making plans.

Instead, I should now have some time for the Norton, who knows I might even manage to refit the cylinder head (which should be on its way back from SRM) and even ride the damn thing.
Sometimes I don't know why I bother anymore.

Sunday, June 14, 2015

A note on fuel consumption.

When I originally fitted the Dynojet kit to my Honda, I made a mistake with the needle, which meant that fuel consumption was horrendously high.

In general, I had thought that the increased performance from the stage 1 upgrade (carburetter and exhaust pipes) would come at a cost in terms of fuel consumption; after all, as Witold says "horses like to drink!".

That said, I am pleased to report that the Honda is returning excellent mpg readings (perhaps because of more efficient carburation and the larger gearbox sprocket): measured in terms of range, I can go about 120 miles before hitting reserve, with a further 25 miles before refuelling. Not bad...

Friday, June 12, 2015

Aaaah.... freshhh.

No, I did not buy a brand new Honda, I just washed mine. What a difference huh? Man that thing was filthy, poor bike!

The fantastic weather we enjoyed on republic day made for the perfect time to finally look after this bike. I went over it with a brush and solvent for the more stubborn dirt, then gave it a... vigorous wash (see what I did there?), and used CRC 6-66 marine spray on all locks and electrical connectors.
I also, finally, got around to making a simple bracket to mount the original small heat shield on the new exhaust headers. The material I had was not really the best so it will probably break sooner rather than later, but at least I know how to make another just as soon as I get some sturdier metal.
Still, I am digging the way it looks now, I'm very happy with it!

Wednesday, June 10, 2015

More photos from the stealth trip.

With absolutely perfect weather for riding and camping out, this turned out to be a very enjoyable outing.

Monday, June 8, 2015

Service and a test ride.

Our GS was due for a bit of a thorough service: all fluids, brake pads/shoes, electrics, carburetters, valve clearances, etc.

As it turned out, it was time to replace a not trivial component: the driveshaft.

These carry a hefty price tag, but then again they cover a lot of ground before they're due for replacement. This one did in excess of 150,000 kilometers. Not bad.

And to test the bike fresh from its overhaul, my folks decided to go on a wee bit of a test ride... all the way to freaking Portugal and back! Ride on guys!

I'm not sure if that's a reflection on dad's helmet, or a particularly good kapalabhati...

UPDATE: in Lisbon now!

Sunday, June 7, 2015

Fitting the new gearbox sprocket.

I got around to doing the "15T mod" as it's known to other RFVC owners. We're a very cool bunch.

Just to recap, I'm replacing the standard 14-tooth sprocket with a 15-tooth one, to increase cruising top speed while keeping revs at a reasonable rate, at the expense of a little bit of acceleration. That said, with the upgrades I've already done, standard gearing feels too low, so this should turn out to be just right.

The sprocket is made by JT and the part number is JTF 308.15. Renthal also make sprockets and there should be one that fits the RFVC engine, (part number 281-520-15) but  I don't know for sure, this time I went for this one.

Using the clever frame design, I put the bike on the jack for easier access to the plastic sprocket cover.

Off come the two bolts, these were a bit stubborn and took some penetrating fluid and a few gentle taps with a hammer to get them to budge.

When it came to taking the chain off I realised that the split link was actually riveted, so I had no choice but to break the chain using my team of skilled negotiators as pictured below... As it turned out, it was really stiff and just about ready to be replaced anyway, so no harm done there. Good job I had bought one ahead of time.

There is a metal chain guide that comes off, and this is what needs a bit of work when putting it back with the larger sprocket.

There simply isn't enough room to fit the larger sprocket, so the chain guide has to be ground down a little bit. The proper way to do this would be to have it machined to suit, but I don't have a lathe and I wouldn't trust a machine shop to do this for me here. Instead, I slowly ground it down with an abrasive disc, checking fit repeatedly until I got it right.
There really isn't a lot of room for error here, and I would recommend being very careful to anyone considering doing this: the chain guide is no longer available as a spare part, so if you stuff it up, that's it.

Then it's on to the two retaining bolts for the sprocket, the very clever locking tab and the sprocket itself.
I wish they were all made like this, this is easy to fit and remove, it's safe and it is simple yet effective: basically once you fit the locking tab over the splines you have to rotate it to align the holes with the sprocket and the assembly cannot come off, because the tab rotates just enough that its teeth won't engage the splines. Brilliant.

Counter to what I know, the face of the sprocket that's marked with the part number and the company logo actually goes towards the engine, whereas I would have expected it to face out. No big deal.

This was also a good time to check the splines on the mainshaft. As it turned out, not too bad considering this engine has essentially done the equivalent of just over two round trips of Jupiter. I know it's a gas giant, I mean the distance...

Friday, June 5, 2015

This better be good...

In an effort to bolster the Honda's performance I have done a stage 1 upgrade with the new exhaust pipes and the Dynojet kit.

There are new tires and I have a DPR9EA-9 NGK spark plug, which is colder than the standard one so I don't melt the head.

All of this is so I can have a shot at keeping up with the others when we go out for a ride, or on a motocamping weekend.

The last thing I can do without exaggerating is to fit a bigger gearbox sprocket to give the engine a little bit more breathing room in top gear.

The stock sprocket is only a 14-tooth, and there is really only enough room to go up one, to 15-tooth.

This is made by JT Sprockets, of whom I had never heard before. While the package boasts "Quality Japanese Steel" and a rising sun logo, they're actually made in Thailand. I hope it's well made, it certainly looks it at first, however closer inspection leaves me wondering if I should be worrying about those marks right on the teeth:

Doesn't look great does it?
Let's see, all I can do is try it. If it works well, I hope cruising speed in top gear will be a bit higher with the engine in its 4.000 rpm sweet spot.

Wednesday, June 3, 2015

Blink and you'll miss it.

That's how quickly Witold put his G/S back to standard configuration at the end of last summer. In the photo below, you can see two engines, the 1000cc on the left and the original 800cc on the right; that's the low-mileage original engine that's gone back into the bike, meaning he stripped everything down: rear wheel, swingarm, gearbox, carburetters, exhausts... the wonderful thing about the '247-type' engine/gearbox assembly, is just how easy and accessible everything is. Replacing major assemblies is a matter of minutes, and everything always fits together precisely, without fail.

This is now a complete and original machine, matching numbers and properly tried and tested, not a showroom primadonna.
Having shed all its touring accoutrements, this now looks like it's half the size it was before! Witold has also come to the conclusion that the 1000cc engine was not very tractable when compared to the original, and everything else "suffered" as a result: the cycle parts became over-stressed, the fork was twitchy, the brakes taxed... Now it has a balance, a harmony that is truly the stuff of motoring legends. This is the motorcycle that announced itself to the world perhaps too discretely, as being a whole new category of vehicle: stable and taut on the road, nimble and purposeful offroad.
If you're interested and would like to buy this bike, leave a message in the comment section.

Tuesday, June 2, 2015

Gone shopping.

This shouldn't be so exciting, but for some reason it is.
I went to a local generic spares dealer and got a few things for the Honda.

There are some spare fuses, clutch cables with barrel nuts, a lightbulb, some fuel pipe, brake pads, silicone gasket paste, a fuse holder and a couple of spark plugs.

One of the plugs is the standard one, the other is a colder one for "high" speed cruising, basically what I should have had on the stealth trip.

These local spares dealers are tough, grumpy folk, perennially annoyed and with no concept whatsoever of customer care: "Nah, you don't want that plug it's too cold." - "Whaddya need them cables for?!" - "That chain is 120 links, sort yourself out or get stuffed!" You get the gist... perhaps that's why walking away with a bag of goodies feels like such an achievement!

Most of it goes into a small bag (together with some zip-ties, lockwire, duct tape, that sort of stuff) that I can carry next time I go camping.

I also got a new 520 chain for the Honda, I didn't think I'd need to replace it just yet, but as you'll see shortly it turned out I actually had to. More on that soon.
The brake pads go in the "service spares" box that I keep at the garage, I'll elaborate on that too at some point.