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Bonneville 741
Continued from the 741 page
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This engine is what any 741 owner (this means you!) can have after a careful rebuild with only pistons and valves upgraded from the original parts and, of course, a modern carb and manifold + good ignition. None of this will cost you more than the stock parts, but the results are so much better. See the 741 page for pistons, valves and manifold. Ignition here (Neil is running a magneto, Lars and Chris IPE electronic).

Chris Ireland (with the "Bella" 741 racer) is working on an "Engine Rebuild for Dummies" article that I hope to post here asap. This will tell you how to go about rebuildng your 741 engine. Chris's engine, Neil's engine, and the one in Lars's "Salt Cracker" (except for the blower stuff) are all the same basic 600cc 741 engine with bigger valves and better carb, manifold and ignition.

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Photo by Pete Lotion 
"We tackled some minor finish-up stuff on my bike and started it up. Very sweet and strong running. We then just took turns for the next day and a half running it back and forth on the practice area to break in the engine and make some adjustments. Wednesday the winds picked up and we decided to wait another year rather than spend sign-up money for only a half day left.

I'm more than happy with the results so far and the CV carb is the clear ticket. I suppose a larger intake manifold would help but it ran super well anyway. We never did really get the bike up to speed since they frown on too much romping in the practice area and the salt was rough as hell and not groomed. 

First gear touched about 50-60 mph [95 Km/t] rapped out and we were easily into the high 70s to low 80s mph [130 Km/t] before we even got into third. 

May have to gear things down a touch but it seems to keep pulling OK as is with 23T front and a 36T rear sprockets. From all accounts it's better to start with gearing too high and not over rev the engine. Also there may be some sense to my light bike theory. A speedway tread rear tire grips like glue to the salt and adding extra weight doesn't seem to be an issue since the tall gearing and small HP won't spin the tire easily."

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                          Photo by Pete Lotion 
The frame is Indian "Vertical" (model 149/249), forks are Velocette girders, front wheel speedway (as are the tires). The rest of the chassis is all Neil's work. Neil is looking into making a new rear frame to take a 22" speedway wheel, to go further along the Tall, Light & Narrow theme. 

This bike is a great example of the fact that all Indians don't have to look the same/use the same original chassis parts (or, in other words, if you have a 741 engine but no 741 frame, use what you have or can lay your hands on!).

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Photo by Pete Lotion 
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I think Lyle, on the 741 (who has a cool 1938 Chief already), is thinking about building a Scout for himself!