Tomos A3K Refurbishment

Hoping to send for the kickstart today.....not the actual casing, just the lever itself, the engine does turn over, but as can be seen the wiring is a mess, hopefully once its sorted, and with the lever on we will see if there is a spark......

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Re: Tomos A3K Refurbishment

The first thing I'd do is clean the fuel tank and look for any holes.

Re: Tomos A3K Refurbishment

Yes, I think it's mostly surface rust, gonna flush tank out and strip the carb. before attempting to start the old girl......

Re: Tomos A3K Refurbishment

u just have pedal arms. lots of info on the a3 here, sit back n read some after a search.

Re: Tomos A3K Refurbishment

It's an A3K.....kickstart model, not pedals

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It might seem an odd question, but where the hell is the choke mechanism on these little A3's ?

Re: Tomos A3K Refurbishment

And also, how do you get to the air cleaner ?.....Thanks

Re: Tomos A3K Refurbishment

♣Slew Foot♣ /

Basicly you got to remove. The top two mounts and gently tilt motor to access the airbox in the frame. Older encarwi carbs have a manual cable choke that fits a choke gate the other have a lever on the carb

Since you're UK. Tomoshop.nl and 50cc.eu

Re: Tomos A3K Refurbishment

♣Slew Foot♣ /

Re: Tomos A3K Refurbishment

Thanks for that.....yes it's an Encarwi carb,.....can't find a cable or lever though.....will see when I tilt the engine....

Re: Tomos A3K Refurbishment

IIRC there is a button on the throttle lever, you press that and the throttle can roll forward a bit which engages the choke.

Re: Tomos A3K Refurbishment

Ah.......just been reading about that, wasn't sure how it worked......Thanks

Re: Tomos A3K Refurbishment

Your gonna want to pull the head and check for cyl/Piston health before you move any further on this. If they are ok your gonna want to upgrade to a dellorto 15/15 carb and intake, that'll get you more power and reliability. And a couple mph. Add a pipe to that and you could gain 8-10 mph. It's easier to forget the stock wiring at this point and hardwire for always on head, tail, and brake light. Just keep a kill switch.

Check your tank interior for rust. If it's bad the frame is comprimised and you'll need a replacement. They have been known to fold into a taco. The tank is very structural (edited)

Re: Tomos A3K Refurbishment

Just been reading up on this choke system.....pure genius !!....although it does say that it can be "troublesome"......can't wait to try it when, or if, we get the engine running....

Re: Tomos A3K Refurbishment

Thanks for that.......the interior of the tank seems fine, just minor surface rust on the outside, although I will be flushing it out.......it's gonna be a while before the old girl is on the road, it does turn over o.k and just wonder if she will fire up, even briefly, a complete strip down is still a possibility.....the comment on the wiring is very interesting......Thanks (edited)

Re: Tomos A3K Refurbishment

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That's the new kickstart fitted, and some oil put into the plug hole, to lubricate things a bit.......the engine turns over real good, next thing is to try and get a spark......

Re: Tomos A3K Refurbishment

You'll want the correct puller which fits the threaded center of the flywheel. Sometimes you can get away with cleaning the points through the window in the flywheel, but with all that rust you're probably going to have to remove it and get everything cleaned up real good. Make sure the cam on the inside of the flywheel is smooth, it operates the points and will wear away the fiber follower if it's rusty.

Re: Tomos A3K Refurbishment

Thanks for that, I have a puller, which I used to use on my old Honda Sky mopeds, it may well fit this one......I understand that the flywheel doesn't have a Woodruff Key, but a small pin ? to hold it in the correct position......might just try and clean points as you say, but really the flywheel needs to come of to clean things up in there....

Re: Tomos A3K Refurbishment

You are correct about the flywheel using a pin, it stands upward with a tiny part protruding from the crankshaft.

Re: Tomos A3K Refurbishment

Yeah the flywheel is held with a tapered friction fit. Pin is for alignment essentially

Re: Tomos A3K Refurbishment

Flywheel pullers come in many sizes and thread pitches. You most likely need one of these, depending on which flywheel you have:

https://www.treatland.tv/puch-bosch-flywheel-puller-p/puch-bosch-flywheel-puller.htm

http://www.treatland.tv/19mm-x-1mm-flywheel-magneto-puller-p/19mm-flywheel-puller.htm

Re: Tomos A3K Refurbishment

Thanks for that....just been looking at wiring diagrams for the A3, some show an ignition coil, some don't......why is this ?

Re: Tomos A3K Refurbishment

♣Slew Foot♣ /

The earlier models all had an internal ignition high tension coil the laters have an external high-tension coil which is what your plug goes to

Re: Tomos A3K Refurbishment

Thanks for that.....so the ignition coil is INSIDE the flywheel ? actually part of the magneto ?.......that makes sense......

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Mmmhhh.......not getting a spark, but I AM getting an intermittent shock from the HT lead, which is encouraging, maybe the plug is u/s.......the points were not opening and closing, but with a little squirt of oil through the hole in the flywheel they are now, the flywheel has definitely got to come off, to allow an inspection and clean up in there.......

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Re: Tomos A3K Refurbishment

I'd bet cash money that if you clean the points through the flywheel window and wired in an external condenser you would get spark.

Re: Tomos A3K Refurbishment

Yes, just going to clean the points, and see what happens.....I'm thinking that if I'm getting an intermittent electric shock from the HT lead, then "juice" is getting through, and the plug must be faulty......just ordered a new one,,,,

Re: Tomos A3K Refurbishment

Typical !!.....the flywheel puller that I have is 24 mm......the one for this Tomos needs to be 26 mm......more expense !! but gotta have it.....the one I'm looking at says it's for Tomos with Iskra Ignition (Bosch Copy) 26mmx1.5.......is that the right one ? (edited)

Re: Tomos A3K Refurbishment

Mmmhhh.......I seem to have a spare brown wire......does anyone know if it's an EARTH wire, and goes to the engine mountain bolt ?........the bolt does have an electrical connector on it.......

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Re: Tomos A3K Refurbishment

♣Slew Foot♣ /

Trace it all but the regulator is ground oh Nd ht coil aka killswitch the one off the regulator is the overcharge dump.

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