Cafe racer bantam-first topic! Woo!

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DAM
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Re: Cafe racer bantam-first topic! Woo!

Unread post by DAM » Thu Jan 07, 2010 12:24 am

Why try and start the bike with the battery disconnected ?
The battery, rectifier and regulator can stay connected, you only need to switch the ignition circuit.

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Greenbat
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Re: Cafe racer bantam-first topic! Woo!

Unread post by Greenbat » Thu Jan 07, 2010 12:28 am

DAM wrote:Why try and start the bike with the battery disconnected ?
The battery, rectifier and regulator can stay connected, you only need to switch the ignition circuit.


But then you can leave the lights on and flatten the battery! :D

I've got a sidelight-off-headlight switch on the LH of the headlamp, and an ignition on/off switch (I think I have an ignition on light for that too :geek: ). I was thinking of having a master key switch, possibly mounted on the side panel. I'd be happier disconnecting both power supplies from the rest of the electrics to make damn sure it is dead and that the battery won't go flat. And I bet I lose the key within hours :evil:

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DAM
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Re: Cafe racer bantam-first topic! Woo!

Unread post by DAM » Thu Jan 07, 2010 12:30 am

Just use a single isolator to disconnect the battery then.
Or use a car ignition switch to switch the battery and ignition line, hats your battery isolator and tea leaf protection combined.

TomC
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Re: Cafe racer bantam-first topic! Woo!

Unread post by TomC » Thu Jan 07, 2010 3:52 pm

Hi Greenbat
I am unsure about this wire you are talking about. The earliest Honda voltage regulator that I am familiar with is a three wire unit that shunts one of the ac corners of the rectifier to ground. One of the three wires is black and goes to switched power. My guess is that there is a small current to ground when this wire is powered. The other two wires are green to ground and the wire that goes to the rectifier.
I have been running my Honda Super 90 with a 10,000 uf capacitor in place of the battery. It needs a good swift kick to start. Also the brake light would kill the engine until I replaced the bulb with a 6 volt led bulb. I am using a home made 6 volt voltage regulator.
If the rectifier and voltage regulator are working properly there should be no need to disconnect them from the battery. Except for the black wire if you have one.
TomC in Ohio

catceefer
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Location: Buckinghamshire

Re: Cafe racer bantam-first topic! Woo!

Unread post by catceefer » Thu Jan 07, 2010 10:13 pm

Why do you want to fit a switch, the rectifier wont discharge the battery so it can be left connected,the regulator I'd expect to be a shunt regulator and won't sink any current when the bikes not charging.


From my experience, they can. Some modern, solid-state regulators suffer from leakage. I wired mine without a switch and found that after standing for a couple of days, the battery would be flat. I confirmed the leakage with a meter. Rather than fit a switch, I used a 12 volt relay. It handles all the current with ease and was very cheap.

Greeno. The bike is looking good. What are you doing about a front brake in he end? Have you given up on the TLS conversion?
Regards,

James.
James Alford
Copper Water Features and Garden Ornaments
www.craftedcopper.co.uk

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Greenbat
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Re: Cafe racer bantam-first topic! Woo!

Unread post by Greenbat » Thu Jan 07, 2010 10:55 pm

catceefer wrote:Greeno. The bike is looking good. What are you doing about a front brake in he end? Have you given up on the TLS conversion?


No, I still have a bit more to do on it. A big improvement was fitting a honda throttle/brake lever/switch unit. It is Very sturdy so does not bend, has a large clamping area on the bars and the lever is a bit longer. Next plan is to alter the wheel end of the brakes so I can fit a thicker, standard jap cable.

catceefer
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Re: Cafe racer bantam-first topic! Woo!

Unread post by catceefer » Sat Jan 09, 2010 11:36 am

Greenbat wrote:
catceefer wrote:Greeno. The bike is looking good. What are you doing about a front brake in he end? Have you given up on the TLS conversion?


Good luck with this. I have given up on my conversion for now. I have a sturdy alloy lever and a cable like a hawser, but the brake was still pathetic. My problem was with the cams and shoes themselves. I might try again after I have the bike running, but for now I will stick with the Honda wheel that I have fitted.

Regards,

James.
James Alford
Copper Water Features and Garden Ornaments
www.craftedcopper.co.uk

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Greenbat
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Re: Cafe racer bantam-first topic! Woo!

Unread post by Greenbat » Sat Jan 23, 2010 5:08 pm

I've been making a battery tray, for a little 12V battery. As the left hand side panel is being left off, I thought I'd better make it look nice, and make it very secure!

Here is the original holder with the tray cut off, the new tray to be welded up and the battery:

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And here is one welded up tray, ready for painting (obviously I've hidden my terrible welding from Pooh!)

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Last night I put the tank on and sorted out the fuel line etc (with a filter). Today I nicked the silencer off the D14, and have ran this one on low revs for a few minutes, just until she's warm. I've been advised to do this 5 or 6 times to start bedding everything in. Currently I'm running her on 16:1 fuel/oil mix, as recommended in the BSA book.
Annoyingly, it turns out the standard pipe won't fit with my rearests. This is even more annoying as I sold IanD a battered one I could have just dented to fit :evil: I think the gear linkage needs a slight rethink anyway, and I still need to figure out the kickstart. So there's a lesson for you-design your rearsets with the rest of the bike assembled!
I had a look under the head, and there was a lot of greyish looking oil. Is the grey from combustion or the cylinder and bore bedding in, and should I be worried? It isn't showing any signs of doom.

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Greenbat
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Re: Cafe racer bantam-first topic! Woo!

Unread post by Greenbat » Sun Jan 24, 2010 7:50 pm

Had a very productive weekend overall :D
Last night I took the wheels off the CG to free off and grease up the brakes. Then I had another look at the gear lever linkage on my rearsets, and the kickstart.
The kickstart has a stop inside the engine so it will only travel so far on a down stroke. It dawned on me that I could fit it so it came down and stopped just before the gear lever, without any modification. This does mean it is at a very strange angle, but it works and starts the bike easily.
I've had a lot of trouble with the link rod fouling on the lever when changing down. First, I turned it down a bit, and removed the spanner hexagon that was the main source of grief. I replaced this with two flats at one end. I also made an ally spacer to go on the engine end, which makes the link run straighter. As well as giving more room, it should be better for the rose joints.

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Today I looked at the exhaust. As I mentioned yesterday, I couldn't fit the silencer off the D14 as it fouled the gear linkage. It won't matter in the long run as I'll make an expansion chamber, but I want to fit it for running in and to get her on the road. The solution was pretty simple. I found a manky front downpipe, and cut most of the way through near the barrel end, on the inside of the curve. I could then bend it so the silencer fits, and weld it up. Unfortunately the welds kept pulling it back together, so I wound up doing this 3 times. Still, it gives it a nice gentle curve. Once it is painted up it'll look OK.
Finally, I made a little ally bracket to hold the silencer on. Not a bad weekend.

Image

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Greenbat
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Re: Cafe racer bantam-first topic! Woo!

Unread post by Greenbat » Tue Jan 26, 2010 8:24 pm

Fitted the battery tray today

Image

I had to move the big shiny horn, as I'd rather foolishly put it where the chain and guard need to go. After trying various alternatives, I fitted the original horn behind the battery on the sidepanel. You can just see it. I also put the reg/rect unit on the other side of this panel, so it gets some air blown over it. I had cunningly made the battery tray offset for this very reason.
Rather less cunningly, it turns out the mudgaurd is in the way of the chain too. I'll be changing how that is mounted anyway, so I'll have to take a chunk out of it too. Never easy is it?

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