Idiot v. Motorbikes, Rounds 3, 4, and 5

[melville]

Little bits. I took a couple days off with Edgar to get out of the smoke and into the warm water:





No clouds, no haze, no light pollution. Naked after 9 in the pools. It's an awesome view of the sky laying back in the warm water once the moon set. There's a bigger pool inside the structure, but why? Sunrise was awesome:



Work did try to interfere with my reverie. I had a client call from Singapore on my way back. My Sena will pick up my phone calls, but doesn't alert me to who they are. I let him know I was on my motorbike 200 miles from home and that the signal might be dodgy. "Hang on a sec, let me get it under 100." I had a signal for the 10 miles the conversation took. Clearly I need to travel to more remote places.

Back in the shop I hooked up the battery and turned the ignition on and the points are pointing and it looks like static idle timing is a few degrees before my TDC mark. Definitely close enough for a start-up. I am feeling the need to open up the bean can to check the points gap and renew the grease on the sliding bit.

Carbs are mounted:



New rubber and the clamps got blingulated on the buffer. I have the clamshell bits, but not the air tubes and it looks like 40mm carbs take a different air tube than the 32s.

[melville]

More progress. I managed to have a key made, which is simplifying things considerably:



All hooked up, it was time to have a look at compression. I ended up with 80ish on the left and 110ish on the right. My guess is that the left side had valves open for 37 years. It left some evidence after turning things over for a bit:



The mufflers are rusted through and will be getting replaced if I'm going to ride this thing even for a few test miles. I still have the adapted aftermarket Harley mufflers that I'd used on Edgar for a wee bit.

I've installed fresh plugs and started buttoning things up on the motor in general.

Parts sufficient to hear the motor roar should be in next week. I'll probably roll it outside for the first start.

[melville]

Things lined up this week. Hansen's got some critical bits in and I had some time to fiddle with the bits. Fuel system in place:



Safety gear in place:



And I had the younger boy ready to act in the case of an actual emergency this morning. But we were denied! The same points that were pointing a week or so ago, weren't, today. So I cleaned them up:



And got ready to try again this evening. I have to say, I actually like the points in the bean can. The gap can be set on the bench while you, the mechanic, stand upright in good light. Downright civilised.

Here's the result:

https://youtu.be/4e3kZTIl_ls

Lotsa stuff blew out the back:



But eventually things settled down, and I did some baseline idle sync:

https://youtu.be/SKb4hmKXGFQ

Not bad for a bike that's been parked since at least:



Next steps are freeing the clutch and then assembling the airbox with parts that are coming. After that, I've got to work out the brake and tire situation for some evaluation test rides. Ernst (my R75/6) may be loaning his wheels and front brake setup for this. Along with his mufflers. I'm hoping to burn through a tank of gas to see what needs to be done before it comes all apart for chassis refinishing and detailing.

[melville]

The clutch was an issue. As I got the bike, the cable moved very freely but didn't seem to be acting on the release mechanism. I cranked up the adjustment all the way and got some resistance at the lever, but testing it, the clutch was not releasing at all.

I pulled the transmission this morning. No real surprises other than this visitor:



I think he'd been in the shop a couple days. He was a bit dried out. I took him outside to where my grapevine gets watered every day and he's recovered. That, and it's rained a bit today.

Shit got real yesterday when the Sawzall came out to deal with the mufflers:



This evening, my son and I pulled the clutch. Here's the lightened flywheel:



And here's why the clutch didn't release:



Yes, that's a disc of friction material that has left the clutch plate. More carnage:



I have a fantasy that there's someone who knows how to resurface the big cast iron piece. At the very least, clutch disc and pressure plate are ordered. I'll have the transmission in the repair stand to check the throwout mechanism in the meantime.

[Jeff in W.C.]

That should buff right out

[melville]

I sent a pic of the carnage to Craig Hansen and he said they had tried resurfacing the cast iron bit BITD and it just didn't work. I can see that--hard to fixture it like an automotive flywheel.

Right now, and for the next couple weeks, is perhaps my busiest time of year for work but paradoxically I get more done because I make a point of stepping away from the desk and into the shop for an hour or so every day. So here's about a week's progress:

I put the trans in my adapted VW engine stand for clean-up:



Scrubbed it all over with a 'red' Scotchbrite:



I took it outside and sprayed it down with etching mag wheel cleaner, then after some more cleaning gave it the soft Scotchbrite finger painting method to get to here:



I did the clamshell also. Left is mostly finished, right is after red SB and mag wheel cleaner:



The method is spraying some silver alu engine paint onto a green Scotchbrite pad and using that to apply the paint. It basically puts paint into the pores while leaving the metal mostly bare. Method credit goes to our own GSPD, thank you, sir!

Nice shiny clutch bits got mounted:



This came up here or on another board. New driveshaft boots are being made with worn-out molds, so the installation directions aren't as clear. Left is brand new, right is from 1979:



Oben is German for 'over' or 'top.' They're also marked for which end goes to trans. Old on the left this time:



Getriebe is transmission, seite is 'side.' Getriebeseite is on the same side as the 'oben' marking. I'm going to be reusing the boot for now as I expect the whole bike is going to come apart for a lot more work after I get addicted to the RS experience.

I've never liked the pin that holds the clutch actuating arm on /6 and /7. It looks like something that wants to fall out. So here's what I do instead:



That's an M8 x 60 screw, a couple spring washers (because German), and a plain nut and a Nylock to jam against each other. Installed, looks like this:



In a perfect world the shank would be closer to a true 8mm and the threads would be shorter but I've run similar on Ernst for over a decade.

The trans is mostly in:



I stopped here for the big work as I was in no mood to deal with the driveshaft bolts but I had a bit of time to change the shocks. Here's old and new:



The shafts on the old shocks are rusty and pitted. I have a fantasy that there's a way to rebuild them as I'd like to keep the vintage mods but I jumped on the Hagons a while ago just in case. Mounted up:



Next steps are bolting up the driveshaft, remounting the battery box and battery, bleeding the front brake that my /6 is loaning, swap the rear wheel with the one from my /6, and do the rest of what needs done to hear it roar again. It could be a few days.

[melville]

Yesterday I bled the front brake. I like to reverse bleed, feeding fresh fluid through the bleeder. The bleeder screw itself has teflon tape on the threads to keep fluid from seeping out the threads while there's pressure with the screw cracked open. Here's the basic setup:



That's a 50cc horse syringe from the feed store. The process starts with using it to drain the MC reservoir and disposing of the old fluid properly. Then tilt the MC so the feed hole is on the high side so any air bubbles go into the reservoir:



The brake is firm and happy now, at least as much as an ATE brake can be.

Craig Hansen mentioned when I was picking up the clutch bits that it helps to run the motor for a few seconds with the trans mounting fasteners just a touch loose and operate the clutch to make sure trans and clutch disc are centered in their axes, and tighten at least one trans fastener while it's running. Apparently the trans doesn't necessarily center when just offering it up. In extreme cases, it can make a sound just like rod knock. I'm always up for an adventure:

https://youtu.be/34Wd4rFvTY0

Turn the volume up if you like--this will be the last time I run this one with open headers.

Looking like this last night after I put the clamshell back together:



Today I've reconnected the choke cables and will probably swap the rear wheel for one that doesn't have a tire from 1982. Then the mufflers go on and it will be time for some test 'n' tune.

[gspd]

Yesterday I bled the front brake. I like to reverse bleed, feeding fresh fluid through the bleeder. The bleeder screw itself has teflon tape on the threads to keep fluid from seeping out the threads while there's pressure with the screw cracked open.
........ The process starts with using it to drain the MC reservoir and disposing of the old fluid properly. Then tilt the MC so the feed hole is on the high side so any air bubbles go into the reservoir.

I'm not a big proponent of the reverse bleeding process, especially when working with used components. Tiny particles of crap or remaining contaminated fluid droplets from the lines and calipers can (and will) get pushed back up into the bore of the master cylinder.
OTOH -Tilting the master (or the the complete bike) or turning the handlebars (with a handlebar mounted master) so the hole is the highest point of the master is mandatory for good results.

[melville]

Rear wheel borrowed from Ernst:



This is not Schoedinger's Cat:



As he clearly exists. But Elsa has Schroedinger's rear brake, existing in the duality of stopping/not stopping. And that's all I'll say about it.

This has to be the wrong sidestand spring:



So I borrowed the spring from Ernst for now.

Mufflers on and the younger boy helping:



It fired right up and was nice and quiet with the mufflers. About 15 seconds on full choke, another 15 seconds on half choke, and then it idled right at 1000 rpm. I had my kid spin it up to 3K rpm and my multimeter showed 14.0 V at the battery. But there's some oil trying to leave the scene on the left cylinder:





I'm going to retorque that side in the morning but I don't expect much.

Otherwise ready for a test or two:



And the ergonomic check:



For comparison, here's Ernst, naked with low bars:



And Edgar, faired with high bars:



I'm interested to see how it feels on the road.

[SteveD]

It'll feel unusual, especially as you're moving from the other 2 setups. Slight lean forward, hips a tad more flexed, hands closer together and leaning on the bars.

Points of difference:
1. The lean forward a tad. The change involves allowing the hands to rest lightly on the bars.
2. Your hands are closer together...narrow bars. This tucks you in behind the fairing nicely, but will feel remarkably different from the RT.
2. The screen height. Judging from your picture I expect you'll get well buffeted! The stock screen height tends to buffer the helmet unless the setup is customized to your height. On a sustained higher speed ride the buffeting is very uncomfortable, tiring, ear ringing. The choices are to buy another taller screen or to trim the existing one. Earplugs f'sure. I've trimmed mine, I'm 186cm...took the top lip off altogether. Much better.

The thing is an excellent package when you get it sorted and acclimatized to it foibles.

Consider an airhawk for looonger rides.

Mine, stock, parabellum.