Bonneville America Forums Forums Technical Forums Performance Mods looking for a little more off the line

I'm currently running an '04 speedmaster. Stock top end, 19" turn-out emgo mufflers, 130 mains, 42 pilots with air/fuel screws at 3 turns and top snorkle removed. The bike has plenty of midrange and top gear roll on, but it can be kind of a hog the first 3000 rpm. I was wondering if any of you guys had any tips to make her a little zippier off the line. Thanks in advance, Bob

The easiest, if you don't already have it, it to use a 16 tooth front sprocket.

I run a 17 tooth, and it pulls plenty hard off the line. You could always upgrade your carbs to a set from Fast Freddy. Here's an informative link... http://www.bonnevilleamerica.com/forums/...ge=0#Post386230

what colour are your plug's when at low rpm's? with the set up you have i'd be inclined to up the pilots
Benny

If you're already at 3 turns out, I would go to 45 pilots. The 04 Speedmaster came with a 16T front sprocket. Has this been changed? The later ones went to 18T. Each tooth makes a noticeable difference. Here's my take: 16 for people who want the quickest starts, 17 compromise with quick start, 18 compromise with better top performance, and 19 for people who care the most about hwy. riding. The extremes give up something. With a 16 you'll be wishing you had a sixth gear, with the 19 you might miss a real first gear.

What years used which sprockets?

Up to around 3000, you are running on the pilot jets alone. Then the slides start to open and you are on the main jets after 3200 - 3400. Around 6800, there is enough air flowing that the idle and transition ports come back online as a power enrichment system.
You shouldn't need more than 2 1/2 - 2 3/4 turns on the idle needles to get a proper idle, so everything points to needing the next larger pilot jets.
Lower gearing always helps low end performance, but it will cost you some top speed. It can cost you some fuel economy, but probably not as much as you'd think. There are some occasions where it can actually save you some fuel.

Thanks guys. I think I'll bump up to the 45's and see where that gets me.

When you go to the 45s, start the pilot screws about 1.5 out and ease out from there, if necessary.