Commando Cafe Racer Rebuild

Poured some oil straight into the intake rocker box and took the main filler cap off. Double checked the feed and return lines to the oil tank were not transposed. Kicked her over again and observed oil returning to the tank in a steady spurts. Blipped the throttle a couple of times and she seems to have settled down quite nicely, even idling. No tacho, so I'll have to see what's wrong there - the cable inner not engaged I s'pose. Ran it for another couple of minutes alternating between blip and idle (cylinder lube is from the crank splash which needs a periodic blip, or so I've been told). All seems quite happy. No silly noises, everything seems fine. Those first couple of engine minutes - man what a stressout!

Got the tacho cable to seat, now have tachometer. Whacked some tension on the chain and took it out into the driveway. Started her up and engaged first and pootled up the driveway under it's own power! Couldn't help myself, went up and down the street 100 metres - in shorts, t-shirt and no helmet or gloves. I was, of course, wearing bike boots for safety reasons.

Running like sh1t though, needs the carbies synchronised and balanced and a dynamic ignition timing wouldn't hurt. Clutch making a bit of noise when dragging, better give that a good look and also check the primary chain tension. Can't forget the sidestand, have to carry the wooden one around which is a pain. I'll go over all these things over the next few weekends. So much yet to do but this is such a humongous step forward.

Er... Woot! I believe the modern expression of joy is.

Didn't get any more time until after tea when I grabbed 10 minutes. Checked the transmission case oil level. It's supposed to take 220ml of oil to fill, so I thought I'd check the level which is done by topping it up. Took a bit over 200ml. So it was completely empty. Now either my engine builder has failed to fill it or it's leaked out in the interim. Maybe the cause of the clutch noise???

welcome.... you have already witnessed first hand the helpfulness and good cheer of this group! They have been invaluable in getting my redneck donor bike up and running. (about 5 years) I dare not divulge the $$ spent in case my wife is looking over my shoulder 8)

I did go the boyer/dyna-coil route and it fired on the 4th kick (much to my wife's dismay)

I can completely relate to that rediculous grin I wore for a week after it started right up...... once I've sorted out a carby issue, I should be good to go for spring.... unfortunately there's a foot of snow on the shed housing the bike......


Take care and welcome

Karl

davamb said:

The coils are 12V RD350 ones wired in parallel.

Click to expand...

Dave,

You can't wire up the coils in parallel, the oscillating circuit will be disturbed and not make as high a voltage on the secondary side. One coil (12v) with dual outputs like the ones on Japanese bikes will give a correct spark as will a pair of 6v coils wired in series.

Jean

Jeandr said:

You can't wire up the coils in parallel, the oscillating circuit will be disturbed and not make as high a voltage on the secondary side. One coil (12v) with dual outputs like the ones on Japanese bikes will give a correct spark as will a pair of 6v coils wired in series.

Click to expand...

Thanks Jean, I'll look further into this. I've set up the ignition circuit as standard with a single ballast resistor feeding the two 6V coils (from Baldrick) as per my workshop schematic diagram and it seems to be running ok.

71basketcase said:

... you have already witnessed first hand the helpfulness and good cheer of this group! They have been invaluable in getting my redneck donor bike up and running. (about 5 years).

Click to expand...

You're so right 71BC, I felt like all you guys were with me yesterday arvo. Weird isn't it. Hope you all enjoyed it as much as I did!

71basketcase said:

I can completely relate to that ridiculous grin I wore for a week after it started right up....

Click to expand...

And yep, I've still got it this morning. Ms Davamb thinks I'm losing it, but so - what's new?

davamb said:

Jeandr said:

You can't wire up the coils in parallel, the oscillating circuit will be disturbed and not make as high a voltage on the secondary side. One coil (12v) with dual outputs like the ones on Japanese bikes will give a correct spark as will a pair of 6v coils wired in series.

Click to expand...

Thanks Jean, I'll look further into this. I've set up the ignition circuit as standard with a single ballast resistor feeding the two 6V coils (from Baldrick) as per my workshop schematic diagram and it seems to be running ok.

Click to expand...

If you are running an electronic ignition with two 6 volt coils, just wire them in series, no need for a balast. If you are using points with 6 volt coils, you will need two ballast resistors, each feeding it's own coil and point.

Jean

Jeandr said:

If you are using points with 6 volt coils, you will need two ballast resistors, each feeding it's own coil and point.

Click to expand...

Why would you need two ballast resistors? The standard points system has a single ballast resistor and two 6V coils wired in parallel.

L.A.B. said:

Jeandr said:

If you are using points with 6 volt coils, you will need two ballast resistors, each feeding it's own coil and point.

Click to expand...

Why would you need two ballast resistors? The standard points system has a single ballast resistor and two 6V coils wired in parallel.

Click to expand...

right you are, there is a single balast feeding the two coils, however, the coils are not wired in parallel, each coil being fed from the balast is going to it's own point.

Jean

Jeandr said:

right you are, there is a single balast feeding the two coils, however, the coils are not wired in parallel, each coil being fed from the balast is going to it's own point.

Click to expand...

In the standard setup, the coils are certainly wired in parallel to each other which was what I meant, and both points sets connect to earth/ground, although each coil is 'in series' with the ballast resistor.

Ok so that's sorted. One ballast, 2 6-volt coils as per the standard implementation. Check.

Now for the tyres. In the interim the as-new K81s have turned to something that resembles Bakelite rather than rubber. Are these still available or is there a more modern recommendation?

I like Avon RoadRiders, and Dunlop 501s, although not sure if the Dunlops are available in a 19" rear...

Hi guys,

been a bit quiet whilst I saved up some $ to proceed further.

So - finally bought some new bits, one of which was supposed to be the gear that has the kickstarter ratchet machined on the inside of it - the thing that the kickstart pawl engages with. They've sent me a gear with splines on it which is not the right part. Can anyone help me with the part number for this and or the correct description to make sure I end up with the right bit on exchange?

Thanks in advance.

That part should be layshaft first gear?

Part 040115

Item [19]
http://www.nortonmotors.de/ANIL/Norton% ... 07&Part=19

Re: Hi from Aus Newbie

Thanks L.A.B.
Judging from the parts diagrams I have I thought it was 040026 (though I did request it as "first gear / kickstart ratchet; P/No 040026"), so it's my fault, I've asked for the wrong part. Dang. Waste of time and money to return the damn thing. Have to be philosophical, it's taken 10+ years so far, another week's not going to kill me.

Re: Hi from Aus Newbie

Hey all,

First up - thanks to those who assisted with the rear hub clearance issue and layshaft gear part number - really appreciate it.
And now to results: progress has been slow over the last couple of months, but now picking up again. I'd saved up for some new bits and they arrived a couple of weeks ago and I've been busy since.
First to get replaced was this hideous chainguard. I think the original was from a CB750 (remember those stickers: British Quality and Japanese Garbage? Rather popular in Melbourne in the 70s!)

Here's the new one fitted:

At the same time I'd refurbished the rear wheel - repacked the speedo drive, cleaned all the rust out of the drum, cleaned the alloy and repainted the hub cover (on the other side). Nice! I could really get to like chrome! So different to my Pantah and TRX.
You can also see in that pic how I made use of this silly walking frame that Ms. Davamb bought me for my last birthday to prop the bike up. Clever huh.

Ha ha ha! Who's having the last laugh now Ms SmartyPants? Huh? Huh! And you thought I was getting senile!
(Joke mode off - thanks darl, it's been a great help.)
I redid the mounting of the stainless rear guard I bought to drop it down and thus clear the Dunstall seat without modifying it or the seat at all. These blocks make a compliant mount that should minimise any fatigue effects. Looks ok methinks. Acceptable engineering, sorry if any pursits are offended - it's never going to be that sort of bike.

Next thing to tackle is to replace the layshaft gear that has the kickstart ratchet on the inside. I'd ordered the wrong gear and had to get it replaced, losing a week. Here's the new gear at last:

This is going to take a couple of night's work to replace...

I've been kicking around the idea of getting the frame Nickel plated. Madame's not best pleased with the idea though. Thoughts?
Also have yet to find a horn and a mirror.

Re: Commando Cafe Racer Rebuild 3 May 2009

Dave, did you also inspect the kickstart pawl that engages with the ratchet mechanism inside the first gear? They often get rounded and can cause slipping. They are not very expensive and I would be inclined to replace it if you are stripping the box anyway and have gone to the expense of ordering the gear itself.

Re: Commando Cafe Racer Rebuild 3 May 2009

Yeah thanks Dave, I did that first. The old pawl was in really bad condition, and replacing it did make quite an improvement, but there must be a couple of ratchet teeth that are, er, really ratsh!t. Pity really, the pawl was a hell of a lot cheaper. Got a pic somewhere...

Edit: here we go:

Re: Hi from Aus Newbie

davamb said:

Acceptable engineering, sorry if any pursits are offended - it's never going to be that sort of bike.

Click to expand...

Of any of the collectible, vintage bikes I've never met a snooty Commando owner. The bikes tend to get ridden for more than other classics and as such they get modified to one point or another. And no one seems to get bent about it.

Re: Commando Cafe Racer Rebuild 3 May 2009

Hi SwooshDave,

I'm not having a dig at anyone, I'm genuinely sorry if any purists are offended because I'm one of them! If I could afford it I would take the bike back to bog stock, but I just can't swing it. Instead I've decided to take it back to the cafe racer it was in its time, but trying to reverse some of the butchery that was done to the poor old girl along the way. If only my wallet was as big as my desires.

This leads me on to another point, I'm beginning to think the bike might have been an "s" Roadster because of the oil tank style (across the frame, not side-saddle) and the lack of a tang on the sidestand. Anything else I could look for to help confirm this theory? If so, it would explain some of the other little oddities I've come across along the way...