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Thanks Adam....Adam_Winstone wrote: ↑Sat Oct 12, 2019 5:15 pm ^... glad to hear that you're liking the change and that performance is more in keeping with what you were initially looking for at the start of this thread
According to the manual on Eden's website https://lambretta-images.com/granturismo-manual/ it states "Timing set at 17 degrees BTDC". As Richard says above 19 degrees with a box exhaust but you are running with an expansion.Hughieboy wrote: ↑Thu Oct 10, 2019 7:29 pmIs it?Burnside wrote: ↑Thu Oct 10, 2019 1:24 pmStatic timing for the GT kits is 17 degrees BTDCHughieboy wrote: ↑Wed Oct 09, 2019 8:56 pm
I was hoping to get it to pull right through the rev range. Unless I’m mistaken, the preferred timing set up is a static 19 degrees btdc to prevent it hitting its ceiling and sort of ‘four stroking’ at high revs. So by using the Hermes CDI it can be set at static timing (or there are two variable settings) that can be used without the need to set the timing high in the first place. I’m guessing that to get 19 degrees at above 5000 revs, say, I would need to be setting the initial timing at about 27 degrees btdc which seems very high. With the Hermes I could set it at 19 static, or switch it to 5 or 7 degrees advanced before 5000 rpm or 2 degrees below (17 static) if needed for any reason.
It seems like a good compromise to retain the Varitronic system but hopefully make it more suitable for the kit.
Or at least that’s how I read it....
I got this from the Lambretta-images GT set up page...
"All ignition systems must be reliable and timed accurately to 19 degrees BTDC (2mm BTDC with 58mm stroke and 107mm rod), electronic ignition is preferable. Barrel studs & threads must be in good condition. Gear selectors, clutch and chain must also be in good condition. Series 1 & 2 cranks with plain bush small-end bearings must not be used..."
Is there something else I should be looking at?
