hey...after a few weeks with the amal kit configuration, i finally ordered and received my amal MKI parts to start tuning it..the stock combination is:Throtle cutaway: 3Needle Jet: 107 Needle position: highestMain jet: 250for memory, the stock jets don't work great on my bike 'cause i got a freeer downpipe and exhaust silencer.i had to put the needle on the highest position because there was a big hole in the acceleration.on this "best setting" stock configuration, the bike is running quite good at low throttle, but as soon as i'm opening the throttle there's not enough power (not as much as there was with the injection).i'll have a lot of tries, will report the various ones...Ben
Ok, so the pilot circuit on the MK1 is the biggest problem that the concentric carbs haves. As you mentioned, the pilot jet is pressed into the carb, which I think is stupid. ..... But honestly, I have never gotten a "good tune" out of this carb, only "good enough". I have never been so disappointed in spending almost $200 on a brand new carb. I will likely be buying a Mikuni VM32 or TM32 (or 2 of each) in the next couple of months. You can actually buy 2 VM carbs for the same price as one Amal.
*Actually the Mk1 isn't bad at all for full-throttle performance. That's why they look pretty good on a dyno. But how often do you get full throttle on the road?
swingarm, i'm not sure if in understand what's your problem at low throttle (let me know), but speaking of low throttle setting, here's my experience...with the 3 cutaway, the bike always stalled when coming back to idle after a heavy ride... very annoying.... (of course the idle was set as it should be)i cured this problem by using a 3,5 cutaway (leaner). the bike don't stall anymore..
Thanks Ben. You've confirmed what I thought the various guides were saying. I've improved the stalling tendency by upping the idle but it's still not trustworthy and who wants high idle on a long stroke motor?