New favourite tool - and a Jawa (Velorex) wheel bearing swap for 17mm axles

As some may know, stock Velorex 560 and 562/700 sidecar axles are puny 15mm items. Which I suppose is totally fine if you bear in mind, that the original Jawa 350 put out 12 hp and even the final Jawa 350 models were in the low 20ies. Now even a restricted SR500 is 27hp and an unrestricted one is at least in the low 30ies. As a result, I swapped out the axle years ago for an old XS400 rear axle and fitted an XS400 rear wheel to the sidecar (thus also increasing the wheel-size to 18").

The new owner of my sidecar also bought a set of wire wheels for those... pretty moments, because to be honest, the cast wheels are very functional, but that's about the end of the story really.

Luckily there's also 6302-bearings with a 17mm inner cage. Swapping out the old Jawa bearings was slightly overdue though.

The first hurdle that has to be overcome is this aluminium cover, which covers the sprocket-drive on the wheel. It just has to be pried off. Normally they are rattly and loose - this one wasn't.

And here it is, my new favourite tool: a 3 Euro hotplate for heating up hubs and bearings. Works an absolute charm as it heats up the parts very evenly. 

Slightly crusty original bearings... 

The only tricky part is this clip that retains the bearing and is usually hid under a stupid layer of crud!

Proper new double-sealed 6302 (17mm) bearing.

And there you have it. The only part missing in the pictures is the part, where I drill out the center-tube to 17mm...

SR500 Hack - bye bye

... and so the story ends for me and begins for someone else.

SR500 hack - swapping an ignition (pitfalls only)

Smug-grin time.

Thanks to my friend Manuel, I was allowed (again) to borrow a complete SR500 ignition to make sure this was really the matter with the old girl.  If you follow the steps outline in this post, it should take you about 30-40 minutes to swap out both the rotor and stator of the ignition.

Marking her territory like a boss.

As you can see in the pictures above and below, the sprocket cover has already been removed and there's a late 48T-ignition sitting on the tarp. 

The only special tool required is the correct alternator rotor puller, which can be bought via Kedo (and probably some others!) When using it, make sure you put a softer copper washer between the puller and the end of the crank (a 1 cent coin is perfect) to prevent it from galling. Also be aware, that between the rotor and the crankshaft nut are TWO washers.

Once the rotor is removed, the stator is only held on with three bolts and you're pretty much on the home-stretch. The factory manual now claims, that you have to remove the oil-feed line from the engine in order to get the harness out. This is not true, it is sufficient to undo the single bolt holding on the oil and then GENTLY bend the hardline outwards a bit. 

Make sure you've put some threadlock on the end of the crankshaft, as a loose rotor will ruin the crank's taper for sure.

All reassembled and I even cleaned away the oil underneath!

SR500 hack - more fault finding

One could really be under the impression, that the old girl just hasn't heard about the signs of the times and simply just doesn't want to leave. The other thing that might be just as true is that as the bike is being sold off to a friend, I simply don't want to take any chances and just make sure it's gonna be as reliable with her as it was with me.

Amongst the ignition, I still suspected the coil to be slightly troublesome, mainly because I did always have some issues with hot-starts and some odd misfiring, which no amount of re-jetting could fully cure. (And after almost a decade of riding Eastern Bloc bikes, I did have my fine share of failed coils.)

Luckily I've bought a new (spare) coil for my old SR a while back from Kedo. It said universal 6V+12V coil for XT and SR on the box and I never bothered to have a real look. Turns out this one runs a different connector and is slightly smaller than stock.

Nevertheless a bit of cunning wiring later and a test was to be conducted. (I then cut off the wiring and plug from the old coil and made an adapter, but somehow I forgot to take a picture.)

And guess what, all the misfires are gone now. Yet still, it cuts out and looses spark when hot and can't be restarted. I'll cross-reference the igniton with some components from a friend's SR500 and hopefully that'll finally cure it.

SR500 hack - She's like the wind...

... as in: she's sold. Naturally the stubborn old girl decided NOT to play along and cut out on her last journey to my workshop. So a bit fettling was due the next day. (Because of course you brake down late in the evening, when it's cold and dark!)

My first suspicion was that the central nut on rotor had come loose, even though I was pretty certain, that I used Loctite last time. (Nope all good)

Then I grabbed a bottle of my preferred penetrating oil to lube up some of the plugs on the bike and what did I find: A little sign from my (better) half... Which now brings up the problem: May I ever throw away that bottle or how can it be refilled?

As a matter of fact, the problem turned out not to be electrical, but way more down to Earth: Fuel filter was clogged up from the water in the tank. (One of the downsides of using the bike in every weather!)

An SR500-carb can be taken apart directly on the bike as long as the patented carb-repair-hammer is used. (Please ignore all the tools on the left in the picture.)

And there you have it: Muffs removed and the bike's ready to go again.

Tricks from the elders: Oiling cables

Every now and then you run into some pieces of ancient cleverness. Nowadays if you want to oil your clutch cable for example, you grab a can of teflon cable lube and oil it. But how did our grandparents do it?

They used a funnel and some rubber hose (which I didn't have, hence the tape) unhooked the cable and filled the funnel with oil and then moved the cable back and forth a bit. As I found out, it doesn't matter much, whether you use fresh or old oil (unless it is all gooey and mucky and comes out of an old diesel - you know the sort!) In this example I used up some old 10W50 fully synthetic, which made the clutch slip in every bike I tried it... 

The cable's uber-smooth now. And yes, I really have to get some proper rubber hose and zip ties.

SR500 Hack - cleaning and dialing in

I think the vehicle that has seen the least coverage on this blog is my SR 500 sidecar. And there's a simple reason for that: it's mighty reliable, which is one of the reasons why I am holding on to it.

The base bike used to be a 1985 or 1986 SR500, type 48T. The frame has been altered in Walcher style, i.e. the backbone has been doubled up and the headstock beefed up. Additionally the rear lower mount has been beefed up with a solid rear footpeg mount off a 2J4-model and some gently applied 5mm steelplate.
The engine is pretty much stock, but with a stainless header pipe and a homegrown muffler, which lets it breathe "a bit" better.

I mostly use this bike during the Winter months and for hauling all sorts of sh*t around and it's extremely capable at that. I haven't encountered a situation (yet), where I had to get out the snowchains... In order to prevent some from eating the old girl up like a hot 'n' greasy hamburger (she's grown a bit leaky over the years), I marinated her with some S100 salt protection spray and I have to say, washing that off left me more than chuffed, but see for yourself.

My dad making sure the Dre-XT-Stück doesn't live up to her name.

The part you can't see in this pictures...

... in order to get the S100 stuff off ...

... we had to use spray-on kitchen cleaner and a hot water jet-wash.

The second part was to adjust to the toe in and pin the lower front mount in place as it had a tendency to twist away, once it was put under enough strain.

About two years ago, I replaced the lower sidecar mounts, which were just normal "clevis" mounts with proper sidecar balls and that was one of the best mods ever done. The little girl is super rigid and can be flung around corners like you wouldn't believe.

The next mods will include a longer sidecar swingarm to fit a proper shock there as the current Velorex-shock's damping is non-existent by now and additionally find some better shocks for the rear as the current Bilstein's are a bit leaky and even before that were softer than I want them to be.