The Sprite project has now started and the first task has been to get the frame ready to use.
The engine has been left in place to make an exhaust and position the silencer. We decided to route the exhaust in a similar way to that of the more recent James bikes doing the rounds. Asking around the concensus seemed to be to use 45mm O/D pipe and a length of at least 30 inches to the silencer in order to get the correct volume so the front pipe has been shaped and welded accordingly. A silencer has been sought and fitted (the end of this still needs to be shaped to point ourwards to the side of the bike at the front of the rear damper).
The two frame tubes that formed a loop at the side of the frame have been cut out and a lower loop welded in place to take a bolt in frame that will move inboard on the frame and allow the exhaust to run down the side of the bike without obstruction.
The tank mounting bracket has been welded in place. We will be using an aluminium tank as per the Mick Andrews replica James bikes.
Next steps will be to add a small piece into the top tubes to sharpen up the head angle by about 5 degrees and the removal of the orignal bash plate sections on the frame to allow for a single ally bash plate.
The rear tubes will be removed from the top mounting point of the rear shock and will be replaced with a much smaller tube looped to offer some rigidity and provide a rear mudguard mounting point.
Pictures show current progress as of today's date.
2 comments:
Dave, I am building a Sprite at the moment with a 37a engine.
The previous owner showed me this site.
I was looking at this picture to see how you did the exhaust.
Can you tell me what the exhaust box is that you used?
Did it work out OK? everyone I speak to seems more intent on performance I would prefer to keep the noise down. I am counting on not needing any kind of expansion chamber.
The silencer was a BSA Bantam one from Alan Wright. It did the job but was not particularly quiet. It really could have done with more volume to be honest - this would have reduced noise and improved performance - hope that helps
Dave
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