6blueoval9
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Is their such a thing for these 2 strokes to adjust timing? And if so, where would one find them?
Adjustable magnet for timing?
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FurryOnTheInside
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Not an adjustable magnet but a small handful of offset keys does the same thing.
The offset woodruff key is the cheap way to adjust the timing, without buying the adjustable CDI.
Jaguar says on his dragonfly75.com site, that 1mm offset gives a 4.5° retard. Ill have to get a degree wheel and check that as my 1.2mm offset key looks like a great deal of retarded timing when it's in the crank.
File a little notch out of the key to make an offset key. You don't actually need the key to be full thickness at the offset bit. As you hold the magnet CCW with your big wrench to tighten the nut CW it's held against the offset in the key.
I bought an offset key made for a scooter/ pit bike (with 1.2mm offset) and just reduced the key's thickness and over all size to fit the magnet and slot in the Happy Time crank.
I could use the kit woodruff key in case I want to try stock timing or something in between. Spare keys for our kits are about £2 for four from China (eBay) anyway, so it's good cheap fun.
In the picture are the tools I used to modify the key (except digital vernier caliper and a table vice), two dremel bits- grinding wheel and cutting disc, and a diamond file.
The offset woodruff key is the cheap way to adjust the timing, without buying the adjustable CDI.
Jaguar says on his dragonfly75.com site, that 1mm offset gives a 4.5° retard. Ill have to get a degree wheel and check that as my 1.2mm offset key looks like a great deal of retarded timing when it's in the crank.
File a little notch out of the key to make an offset key. You don't actually need the key to be full thickness at the offset bit. As you hold the magnet CCW with your big wrench to tighten the nut CW it's held against the offset in the key.
I bought an offset key made for a scooter/ pit bike (with 1.2mm offset) and just reduced the key's thickness and over all size to fit the magnet and slot in the Happy Time crank.
I could use the kit woodruff key in case I want to try stock timing or something in between. Spare keys for our kits are about £2 for four from China (eBay) anyway, so it's good cheap fun.
In the picture are the tools I used to modify the key (except digital vernier caliper and a table vice), two dremel bits- grinding wheel and cutting disc, and a diamond file.
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crassius
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also, there are two different rotors now - older one for unbalanced cranks and newer for newer cranks - slots are about 5 degrees different
older CDI units (the ones with only one connector on each wire) are about 5 degrees advanced over newer CDIs
older CDI units (the ones with only one connector on each wire) are about 5 degrees advanced over newer CDIs
FurryOnTheInside
In Memoriam
So this CDI being newer means that I have followed old information and didn't need to make a 5.4° retard timing key? Son of a retarded bit.
Oh well that's MB building
Street Ryderz
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It's all good if you retarded it 5.4 degrees and your cdi has 5 degrees retarded thats 10.4 total from the 23-25 it started at so now it's at 13.4-15.4 much better since ideal is 8-10 degrees and as the rpm climb now at the peak instead of being around 30 degrees now you will be at 20 degrees not ideal but better at least.Also I dont think the cdi is retarded any it's just the different keyway locations if your magnet has the one oclock keyway position you did the right thing the newer ones have the keyway closer to twelve oclock and that's where the timming difference is.So this CDI being newer means that I have followed old information and didn't need to make a 5.4° retard timing key? Son of a retarded bit.
Oh well that's MB building
View attachment 79101
FurryOnTheInside
In Memoriam
I will see if the CDI that came with the kit feels different from this one which I think is the spare I bought separately. Pity, it means rewiring to get to the definitive answer.
I will have to try to get a newer magnet too..
Street Ryderz
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Why not every bit helps right.
FurryOnTheInside
In Memoriam
Hold on.. if newer magnets have the keyway closer to 12 o'clock then they're relatively advanced. My magnet keyway is definitely at one o'clock and I have changed the key to a more 12 o'clock position to retard it so something is not making sense.. Idk if it's me, I'm very sleepy right now.
Street Ryderz
Well-Known Member
Thats right the crank turns clockwise and shifting the keyway back towards 12 oclock is the same as you cutting the key to allow it to shift back more towards the 12 oclock.Right now my keyway on the crank was filled and then recut 7 degrees retarded and I use the 12 oclock magnet for around 12 degrees total and my engines fixed timming is around 11 degrees btdc and I found the torque increase was alot look at how numericaly low of gear raito I run and it out pulls stock bikes even some mild modded ones but then keeps going lolHold on.. if newer magnets have the keyway closer to 12 o'clock then they're relatively advanced. My magnet keyway is definitely at one o'clock and I have changed the key to a more 12 o'clock position to retard it so something is not making sense.. Idk if it's me, I'm very sleepy right now.
FurryOnTheInside
In Memoriam
Sorry but I'm going to be pedantic and press this point even though I don't have any alternative magnet lol, even after a bit of sleep I am still certain that the magnet having the keyway closer to 12 cancels out the effect of having the key offset closer to 12.
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