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Daves mods

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I am really considering doing the Daves mod to my 650l and i have read almost ever post on here about it but I have not seen where to get the needle shims or jets from. If anyone has any suggestions please throw them my way


Sorry if this is a repost. 

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I used to be in the "Stock Jetting" club like you.

I bought mine new, and the owners manual said "Don't make any modifications to your Honda motorcycle".

So I rode it for a few thousand miles stock.

Pulled the plug at 5000 to 7000' elevation, and it was on the lean side of the tan color.

Even at that elevation it was surging (lack of fuel) and difficult to ride.

I pulled the plug at 0 to 1000' elevation and it was absolutely ASH WHITE.... I was stunned...

So, the first thing I thought was that all that stuff they say about it on thumpertalk is true....

Went to Jets R Us, replaced pilot 50s with a 52, replaced main 152 with a 155 and opened up the airbox.

Shimmed needle to .035", drilled the slide (Only one hole) with a 5/32" drill, I did all of this in stages to see what each parameter did at a time.

The jetting was by far the most dramatic, no more surging, easy starting, easy to ride bike.

BTW, my bike is BONE STOCK (never had the valve cover off, just the adjusting ports)

And, the results of the Jetting:

At 5000 to 7000' it's a pinch rich, runs like a dream under all conditions (high load/rpm no detonation)

At 0 to 1000' if you're on it real hard like 6000 rpm up a steep hill, it will detonate, so at sea level this combo is a tad lean.

So my solution was to go 3 full turns out on the fuel screw and run 91 octane, and it solved the detonation problem, but just throwing it out there, that at sea level 52/155 might be a tad lean.

Results may vary, just my experience...

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