Wednesday, 23 August 2017

The XS Triple Sidecar - fusebox

One of the things that can really make or brake your experience with a bike is reliable electrics. And one of the most overlooked parts of said electrics are fuse boxes. Old grimey fuse-holders often lead to dramatic drops in overall voltage or even no voltage at all. Cleaning the contacts is a good temporary solution, but when you realise that one of the tabs is actually broken and that's why your headlight is more like a candle in an old lantern there's an issue that has to be addressed.

The amount of space under the seat is "a tad" limited, so a fuse box with side-connectors had to be used.

The stock fuse-holder with glass fuses and not one of them being of the right specification...

And that's the new fuse box wired in and boy is that headlight bright now...

The other thing I really had to tackle was the lack of a breather filter. Opinions on these vary, but I am pretty convinced, if it is oiled up properly it will not aid condensation inside the engine. Now of course I couldn't get one (locally) that would fit straight out of the box, so I had to fire up the lathe and make an adaptor:

The red K&N-oil will add at least 10hp. 😉

Last thing missing is the steering damper mount, which you will see in one of the next posts.

Friday, 18 August 2017

Project "pretty one" - pulling the engine out and finding the fault on Dre-XT-Stück

Sorry for stuff being a bit jumbled up chronologically, when this post comes out it will actually look back two weeks to when this actually happened, but a lot has happened since and probably even some more will, as I am still head over heels in doing all the legal work to get my sidecar on the road.

With that being said, right after we got the sidecar outside of the workshop my dad asked me, whether we could pull the engine out of "pretty one", so he could attack thirty years of dirt and grime and have the engine on the bench at the same time, so further investigations can take place.

Taking the engine out on a XT 500/600 4 Valve is a pretty straight forward process: There's one mount on the head, a double mount on the front and the swingarm bolt and one bolt below make up the rear mounts.

A small car jack makes things a lot easier and means you could theoretically even do it alone. 

And that's the engine out and on the bench for further investigation.


After that we put a rag over the engine and parked the pretty-one somewhat closer to the wall and decided to swap out the stock carb of the Dre-XT-Stück with the one from the "pretty-one", which also mandated swapping around the inlet-rubbers.

And guess what: Nothing. Same issues as before. So it was pretty clear that it wasn't (only) the carburettor that was causing the trouble, but something else. But I did note, that it would pull cleanly for a short while and then stall. So I decided to renew the fuel line and replace it with a longer hose in a sweeping bend.

Let me politely say: F*ck you hose! F*ck you stock carburettor! F*ck you my own hybris for taking a short cut with a short piece of hose and being sure that it would work alright.

With the old Dre-XT-Stück now running like a scalded cat (a bit rich perhaps), we even went as far as to add the missing left side panel (and peel off some of the old stickers!)

Wednesday, 16 August 2017

Building a DB-Killer that actually works

Most of those universal muffler-tip inserts you can buy out there are all nice and good, if you're *JUST* over the legal noise limit. Now my exhaust on the TR1 and on the XS-Triple-Sidecar weren't a bit over the legal noise level, they had to be silenced quite a bit - which meant around 20db on the TR1 and I didn't check on the XS Triple Sidecar, but it was around the same amount.

That being said, the main flaw of most muffler inserts is, that they don't force the exhaust gas around corners and thereby don't reduce the speed of the escaping gas sufficiently. I sought to change that with this relatively simple design.

I used some big washers turned down so I could weld them to the inside of a tube that would go into the slip-joint of the muffler. 

Cut two lengths of tubes that would fit inside the center hole of said washer and made a plug on the lathe, which would go between said tubes.

And this was my first prototype. The holes were ground with an angle grinder and relatively large compared to the actually used inserts. But it proved a quite dramatic noise reduction was possible.

Without an insert the TR1 was idleing at around 82 to 84db and the amount achieved, with no further damping material (i.e. stainless steel wool pot cleaners) was below 70db. The measurements were taken 1m behind and 1m to the side of the exhaust.

So how does it work: The exhaust gases come in through the center hole, escape through the first hole, have to go all the way round to the other side and escape through the bottom hole. All of which results in a massive reduction of gas-velocity and thus less noise.

In order to make the legal side of things easier on me, I decided to weld them in completely to make sure that during the inspection the engineer wouldn't add a line saying something like "removable muffler-insert" to my papers. As that's what the police always checks first overhere.

Another setup I tried before and which (to my surprise) worked better than expected, were these really simple inserts, basically just comprising of a large washer with a 20mm hole. If you're a bit gentle on the throttle the noise levels up to around 3000 - 3500 rpm are nearly the same (you'd have to have both bikes sitting next to each other to really make out a difference), but especially at higher rpms it's lacking dramatically.

All of that being said, the first set of GreasyGreg Exhausts has been entered into the legal paperwork of my bike and it will certainly not be the last.

Oh and if you're worried, don't the actual registration code of my exhausts is quite a bit longer than that... This is only the "model identifier". Pretty posh, eh? 😎

Saturday, 12 August 2017

Legalize it! (The XS Triple Sidecar and the TR1 that is...)

... not talking about any psycho-active substances. As the regular followers of this blog might have noticed, apparently some of my stuff was getting pretty close to the mythical state of "done". And in fact they have. On Thursday I had set up my appointment with a government engineer to check up on both the Tractor (everyday TR1) and the XS Triple Sidecar. As is custom with such dates, all of a sudden lots of issues and niggles have come out of the woodwork and meant that from Tuesday evening onwards I was burning a lot of the old midnight oil.

On the TR1 the main goal was to finally declare all the mods done to it and finally run it as legal as technically possible. Except for muffling the exhausts (there'll be a separate post on those muffler inserts "db-killers") there was also the issue of mounting the numberplate and rear light at a steeper angle to comply with local law.

I proudly present the world's chunkiest, billet aluminium numberplate mount. Solid enough to lift the whole bike with it. 😏

And that's the muffler tips in question. Believe me, when I say they work waaaaaay more efficiently than I wanted. (The TR1 is now 7db less noisy than a stock bike. You really have to use the tach to make sure it's running.) But hey, it got me through inspection and the bike's performance hasn't suffered too badly. So in the long run I'll open them out a bit, but other than that... Interestingly enough they also improved the low-end torque quite a bit and helped to smooth out some slight transition issues from pilot jet to needle.

Now of course the XS Triple Sidecar was the bigger challenge. Firstly the sidecar's suspension had to be set up correctly.

The forks were pushed too far through the yokes, resulting in a rather nervous driving experience.

The front mudguard had to be drilled as it's off an XV750 and the holes didn't line up perfectly resulting in a weirdly high mudguard.

And then there was a little pet-project: I wanted to have the choke control on the bars. Which is quite easily done, if you have a set of TR1 or XV750 handlebar switches, as a stock TR1 has got exactly this lever on the bottom of the left control. The switches are all the same, so you can just swap the casing around as you like, resulting in the Turbo no sporting a clean switch with no choke lever and the XS Triple Sidecar being exactly as awesome as it is.

Of course I also had to install muffler tips on the XS Triple Sidecar and in the long run I'll also install an H-pipe to link the two long rear pipes, because the exhaust pressure is really, really high resulting in the XS nearly being louder than the TR1.

Probably install that H-pipe right somewhere overhere, where the twin pipes are joined into one on each side. 

Sunday, 6 August 2017

The XS Triple Sidecar - Outside

This isn't so much a highly technical, but more a motivational post. I've finally managed to get my XS-Triple-Sidecar out of my workshop. (Which does in no way mean, it's completely done!)

And that's what it looks like outside (admittedly in the gentle evenning sun):

Oh it's looks pretty finished you say. Well, can't argue with that, it's mostly small stuff: fit mirrors, make some spacers to increase the pre-load on the forks, fit my home-made db-killer-inserts, fix the broken choke lever, maybe check the alignment once more and of course have a few more testrides around the house of course.

Friday, 4 August 2017

Checking clearances on a plain bearing crank

Now my mate Carl didn't only buy one XS750, but two. Unfortunately he got taken pretty well from behind with the "valuable" spares that were included with the second bike, so an afternoon of spreading the chaff from the wheat was due. Or in other words see if he did in the end get enough parts with the bike to build another engine.

Part of the deal was this crank-case-combo, which obviously never ran together as all the markings on the cases and the crank (look it up in the Haynes, it's quite well explained) were way out of spec.

Rather unsurprisingly, even with the cases just nipped down a bit the crank was stuck.

Luckily there was a second (partially f*cked) crank included. The bearing shells on the middle rod were pretty much gone, but luckily Carl had received a box full of old conrods, which meant that we shuffled them around until we found a good one to go in the center-spot.

A bit of plastigauge later and it is confirmed: Slightly over spec, but well within tolerance for farm-equipment! 😉 Btw. as a rule of thumb: If the bearing clearance is around 1/2000 of the crank-pin diameter, you can't be too far off. (Always consult a manual of course, but if you do and check the specs you'll find out that you usually land somewhere in the middle of the tolerances.)

And lastly: You don't always need plastigauge to confirm (roughly), whether a crank is in the right ballpark or not. A bit of oil and a bit of spinning can you give a pretty good indicator, if it's going to be alright or not.

Wednesday, 2 August 2017

Ms. Braaaaaap - dressing up

Ever since I resurrected Ms. Braaaaaap, I decided that contrary to my normal belief, I'd also do some cosmetic work on the old girl.

One of the things I completely stopped noticing was that the cylinder head was a bit cosmetically challenged.

Which was quite easily remedied with a bit of heat resistant paint and a file to clean up the cooling fins on the engine.

The pictures don't really do it justice, but I do have to admit it looks nicer and the bike looks a lot more tidy than before. But Ms. Braaaaaap is a cruel mistress, was she greatful for me taking care about her looks? Nope. The rear tube is flat (probably damaged during the tyre install) and she now sports an odd misfire and then she invariably cuts out, which is either the coil or some blockage in one of the carbs air-passages. Well, I was planning to spend a bit more time wrenching on her, so I guess she'll get her will...