Cafe racer bantam-first topic! Woo!

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

Unread post by Greenbat » Sat Jun 05, 2010 2:28 pm

I put a few in the "what did you do today" thread. There's several on my flickr thingy here: http://www.flickr.com/photos/35741071@N03/

Here it is at Wetton Mill: Image

Just had a play with it. New plug made no difference, so I tried changing the carb bits again. It was running perfectly on a 108 main, 110 needle with needle on the leanest groove and a no.4 slide. I've gone to a 107 needle jet (still with the needle in the top groove) and the original 3 1/2 slide. New plug is going a nice brown colour after a short run. Good news is the slide no longer sticks, meaning I can fully open the throttle. This does seem to choke it up, so I'll have to look further. Still puzzled how it can go from perfect to far too rich overnight.

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

Unread post by sfb » Sat Jun 05, 2010 2:47 pm

Lovely!

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

Unread post by catceefer » Sat Jun 05, 2010 6:37 pm

Greenbat,

Thanks for the flickr link. It certainly looks good and I am pleased that the brake has proven worthwhile.

Regards,

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

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

Unread post by Hooli » Sat Jun 05, 2010 8:04 pm

Dodgy float? If the float level rises that makes them richer dont it?
Classics ain't built in Metric

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

Unread post by sfb » Sat Jun 12, 2010 12:42 pm

I've found the high-level bantam pipe, Greenie. It needs a bit of cleaning up but it is basically in good condition.

Do you want it sending?

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

Unread post by Greenbat » Fri Jul 23, 2010 2:26 pm

Finally fitted the expansion pipe. I've made it so I can adjust the length of the header and fit different bleed pipes. Tried it very carefully up the road and back and it seems more eager to go-though it is very loud! I'll have to beg, borrow or buy lots of amal jets before I can set it up properly though.
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lazybandittattoo
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Re: Cafe racer bantam-first topic! Woo!

Unread post by lazybandittattoo » Wed Dec 28, 2011 9:56 pm

Expansion chamber looks good.

Did you get to the bottom of your carburettor jetting and over richness?

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

Unread post by Greenbat » Wed Dec 28, 2011 11:12 pm

lazybandittattoo wrote:Expansion chamber looks good.

Did you get to the bottom of your carburettor jetting and over richness?


Had a play around with it, apart from being obnoxiously loud it wasn't a vast improvement-think it was more a moped chamber. I had better luck with a suzuki X7 pipe, then a KH250 spanny pipe (back to loud again :D). X7 made a nice bike, reasonably quiet too. Only problem is I'm using a narrow bore high level downpipe, as I don't have the bigger one. After that, I think next thing is a better carb.

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

Unread post by lazybandittattoo » Thu Dec 29, 2011 1:14 am

I'm messing with carb experiments myself. I tried 32mm but it was too much I think. Using a 26mm carb now and it seems ok. Have jetted it 150 main jet and 105 needle jet as per bantam D14 handbook for now.

It's running with a 64mm piston and the smaller 21mm carb (and D7 Barrel) lead to over richness - air starvation. I picked up a barrel with a 26mm inlet. I'm interested to know what jet sizes you settled on and what size carb/ inlet you are using.

I too am still using the smaller bore exhaust.

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