So these fiber boynesean reeds are not flush with the Reed block. And this is after flipping them. Ie they are open a bit. For comparison are oem never used. Could this be the culprit of hard start.
Make reed springs out of old metal reeds to press your reed down. They cut pretty easily with sharp scissors.
Bend them so they press the reed against the block.
Sand em smooth afterwards
Stock Reed no difference. Still needed prolonged drill start to catch. And they don't sound as good as the fibers. So not sure if I learned anything. And yes if the reeds were the problem your mods would help the fiber. Your carbon reeds look great. What did u cut them from ?
Those unclosed Boyesen are not going to work whether it's the hard start issue it not. I'm guessing you tried to tune around semi open reeds so your jetting from idle-1/8 is probably very far off
Dillon: the bike went from easy start to hard start when I switched the head from a old motzig head with decomp to a treats 44 mm Puch/Hobbit head and a pull start. Assuming for a minute that there isn't some airleak etc is it possible that the decomp head when pedal starting and suddenly closing the decomp valve creates enough back pressure to slam the sightly open reeds totally shut for the instant of ignition and once that happens presto cold start. Now I can still start it often but only after drilling it for what seems like way too long. The motor catches and runs very well. Once hot it can be often started with the cheetachrome pull start.
Pressure will close the reeds, but they are supposed to sit flat, without question. That is having an affect on your starting.
You probably have a head air leak.
Sand both the cyl and head on flat surface, my bike did the same thing when I had an air leak with a puch head.
As well, did you add enough spacers to the bolts so you're not bottoming out the cyl bolts into the cases? I had to add a lot of spacers and add modded cut washers between the spacers and head to distribute the tension.
When I used spacers alone they dug into the aluminum slots and created an air leak
I've got 125 psi on a compression tester. I changed the m7 studs to a 97 mm so the long mallosi nuts don't bottom. But I agree something is rotten in Denmark and I will have to at the least pull the head off and recheck it's flatness on a piece of tempered glass. I'm probably going to prove it pedal starts by putting the original head back on. I thought this upgrade would be a walk in the park. Unfortunately the park is overrun by Gremlins. The way the head is slotted the nuts are super close to the fins which required thinning the fins to give room to torque. The nuts were easily torqued to 105 inch pounds. It was only after hitting my head on a wall repeatedly that I came up with idea of inspecting the reeds for gap. I tried the oem Reed block that the metal reeds sit flat with the same difficulty to start and also found a set of carbon single stage reeds which I can try but I am now thinking the pedal start nonsense I mentioned above is actually what's going on. Btw I'm using a 15 or 16 can't remember Sha on this bike...I've used it for years. I changed the slide to a #2 thinking it might have better draw when at idle .. vs the slide it came with which has a square notch at the bottom. Jet is a 74. It's a stocko shocko that I had a local guy correct all the out of square issues at the base gasket and the deck. The kit is raised with a mlm plate so the transfers clear at bottom dead center. This was not a haphazard build until my last go at it. Very frustrating because I swore I would get this right before I went on to my next project... A water cooler. I don't want two miseries at one time.
Cut the head for more room for the nuts and washers, and cut washers to look like a pizza slice with the hole at the eatin point
My hobbit was recently very hard to start. Had a gila head on it, bing, boysen reeds, the whole deal. i went crazy trying to figure out what it was....turned out my plug was fouled....
Ok somebody please explain the following: seeing that the additions of the cheeta pull start, the treats ouch 44 mm Hobbit head , and the Reed stuff has been noted; I put the original head with a decomp ( an old motzig head milled from a stock Hobbit head) back on. Didn't even hook up the decomp and pull start zip nada rien buuuut pedal start one or two spins roars to life! Off and pull start nada , back to pedal ahh roars !
Yes I didn't take off the starter shoes. That was coming.
Question : why spinning the house mini flywheel doesn't work but spinning the motor via the other side or the various side works ?????? And yes the pull start spins the engine. I'm assuming the pull start is spinning the engine clockwise.
In all honesty it's probably your tuning, try cracking the throttle as you pullstart. I do that every time I pullstart
Jbot : I assume u ditched the starter shoes? I'm thinking the starter shoes are acting like a brake on the pull start and on the drill start ! Whereas with pedal start they have momentum stored in the clutch.
Of course. Why are you trying to pull start a bike with starter shoes?
The starter shoes should only grab if the back wheel is spinning. You should be able to pull start still.
the new head probably not sealing, but that doesn't answer why it wont pull start with the og head....hmm.
So next step is to pull starter shoes and see if the pull start works to cold start easily.
News flash: pull start works on the bike with starter shoes off with old motzig head. Next step treats Puch 44 head after I check it for any out of flat. Then I'm putting in those skanky slightly open reed block. Maybe have cheeta put in the wiki the obvious: take starter shoes off before seeing how it works.
Treats head , no starter shoes, cheeta pull, stock reeds = start first pull.
Next the scanky sort of open reeds.
Still take home message is obvious.
Pull start + no starter shoes + puchhobbit treats head+boynesean reeds that have a slight gap + everything else = easy start.
The starter shoes will both start with a pedal crank and will also stop the engine from catching if they lack momentum transfered from the pedal chain. Yes under some conditions the starter shoes will allow the motor to catch just with the pull start at times but the starter shoes act as a brake.
Unless your springs or shoes are in rough shape (sticking or weak springs) the starter shoes should never make contact with the plate inside the bell while pull starting.
Ryan: how would you validate your statement of fact. It sounds like some kind of truth. And yes this old clutch deal is probably not pristine. It's a pa50 1 bell etc because when I built the motor my friend who helped me thought the past 50 1 crank looked fabulous. Yes I'm aware of the tendency of the crank to shear off and that's why it's a mild mild build with only a notched stock vario not something developing more torque. The bike is a low 40 solid ride.
Here is a photo of the starter shoes. Nothing looks worn to me.
Those springs get stretched every minute you're riding the bike.
I bet they are very very weak.
They also fuck up real clutch stall at lower speeds. Throw them in the trash
If it wasn't raining I'd take it on i 80 to SF. .....
As a point of fact, the starter clutch is not in contact with the starter plate when operating properly. The fact that without a belt on your clutch should spin completely freely with bearings that are not trashed. The shoes only make contact when the bell spins fast enough (by pushing or pedaling the bike) to throw them outward and engage. When pull starting or drill starting the clutch bell is stationary.
So removal of the starter shoes in this case is evidence of a moped miracle?
No, somethings fucked with your setup allowing them to make contact all the time.
Either clutch bell bearing probs, or swollen pads, or sticky reside on the clutch plate
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