Installing hpi mini rotor on a hobbit

The treats shows the cable off the stator coming forward and not being routed through the hole in the back where the oem stator output is routed. The connector to the cdi box is bigger than the diameter of the oem hole. Have people enlarged the hole or just brought it forward?

Re: Installing hpi mini rotor on a hobbit

You can disassemble the plug with a tiny screwdriver. Each individual wire has a tiny clip holding it in once you take off the red plastic piece. Then slip the wires through and rebuild the plug.

Re: Installing hpi mini rotor on a hobbit

Ok I looked and wasn't sure of that. Thanks jake.

Re: Installing hpi mini rotor on a hobbit

I just enlarged the hole ......worked fine

Re: Installing hpi mini rotor on a hobbit

For future generations...

Here's a picture from Marc, you stick a tiny flat screwdriver in the plastic slot above each of those metal connectors in the picture and push the tip of the screwdriver down. As you push down, pull on the wire and it should slide out the back.

Re: Installing hpi mini rotor on a hobbit

Remember it's above the female connector. Not below as pictured. And when we say the wire slips out its actually the wire and the female connector. Shine a bright light in and see the tiny area above with the plastic above and the connector below. It literally pops off so if you are tugging you haven't popped the retainer off NEVER. PULL HARD. !!!

Re: Installing hpi mini rotor on a hobbit

RADIUM CITY JO$HUA /

I also enlarged the hole.

(edited)

20130226_083720.jpg
20130226_091017.jpg

Re: Installing hpi mini rotor on a hobbit

3 ways to solve one problem.

One giant leap for mankind.

Re: Installing hpi mini rotor on a hobbit

Ok so next question: so the stator and the rotor have marks. If you set the two to tdc as in the instructions then is the firing point start tdc and then it further retards as rpm increases or is the unit designed to start the firing point at a more advanced point. Obviously I will check this with a timing light if all goes well later this morning. I was planning on a start at 18 degrees before tdc as the stock setup works and check temps and performance from there.

Re: Installing hpi mini rotor on a hobbit

You set the piston to 2.5mm btdc and put a piston stop in to stop the crank from turning, then line up the mark on the flywheel with the correct line on the stator plate, then tighten the flywheel nut.

Re: Installing hpi mini rotor on a hobbit

How many degrees before tdc is 2.5 mm

Re: Installing hpi mini rotor on a hobbit

Re: Installing hpi mini rotor on a hobbit

Jake. Did you get good temps at 2.5 degrees before tdc?

Re: Installing hpi mini rotor on a hobbit

Yep. It retards a lot when the motor revs up, so the timing drops to about 15*.

Re: Installing hpi mini rotor on a hobbit

If someone has a unmounted stator could they please accurately measure the circumference and or the diameter. I want to put on a degree wheel on the stator.

I aligned the two marks ie on the stator plate and the mini flywheel to true tdc. The idea of accurately measuring the piston from tdc through the spark plug seems a bit difficult. Then I rotated the stator plate counterclockwise and got my Athena fired up and running. So I know it's some number of degrees before tdc. I really want to start atm18 degrees before tdc as in the stock setup. And check temps and plug chops and in addition measure the retard ignition curve. It sure would have been easy if they actually machined in a degree wheel.

My temps were too high at wot so it is quite important to do this step, I think.

Re: Installing hpi mini rotor on a hobbit

Setting it at 18* at idle defeats the point of the Hpi.

Re: Installing hpi mini rotor on a hobbit

Why? Please elaborate. Do you know the exact hpi curve? Can you send me a link to their data points?

Re: Installing hpi mini rotor on a hobbit

So I am looking at a hpi curve on google images. At 200 rpm it jumps to 30 degrees and advances from there. So if this were true than the starting point needs to be very very advanced or you will be getting spark way way past tdc. Or I am totally wrong!

Re: Installing hpi mini rotor on a hobbit

It retards. It doesn't advance.

Re: Installing hpi mini rotor on a hobbit

Marc Friedman Wrote:

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needs to be very very advanced or you will

> be getting spark way way past tdc. Or I am totally

> wrong!

this would be true if you were actually spinning 16k or so rpms. not many of us are.

I'm gunna take a wild guess and say you're gunna get around 12k rpm revving on the stand, so you're looking at 10 degrees of total curve.

HPI tells you very clearly in the instructions where the "Fire Mark" is but they don't tell you what that means.

it's my impression that the "Fire Mark" refers to this portion of the curve:

Re: Installing hpi mini rotor on a hobbit

I am going to find out for sure this week and post my findings. The problem is the crummy rpm gauge I have wrapped around the spark plug wire. I need a better rpm gauge. I am going to look and see what's at auto parts store.

Re: Installing hpi mini rotor on a hobbit

Marc Friedman Wrote:

-------------------------------------------------------

The problem is the crummy rpm gauge I

> have wrapped around the spark plug wire

how so?

Re: Installing hpi mini rotor on a hobbit

It ain't accurate.

Re: Installing hpi mini rotor on a hobbit

Hey jake.. Did you get that conversion chart off a website?

Re: Installing hpi mini rotor on a hobbit

So they got back to me at hpi. When the stator and mini flywheel is set at the piston off from tdc at 2.8 mm ( or whatever it exactly says in the instruction link at treats) the initial low rpm is 26 degrees before tdc and it peaks at 5 degrees before tdc.

The exact message is "26 til 5 degrees retarding"

Re: Installing hpi mini rotor on a hobbit

Will, yes. It's a link in the wiki. You punch in the connecting rod length and stroke and it gives you the option of selecting the step size. (edited)

Re: Installing hpi mini rotor on a hobbit

Jake I am beginning to understand the simplicity of actually measuring the piston 2.8 mm from tdc and aligning both the mark on the flywheel and the stator. My buddy has the real tool. I will have to borrow it. I visually thought And found tdc and set the mark on the flywheel and stator to that out of ignorance. I also put a mark on the case. If my timing is right the stator mark should be 26 degrees from both the case and the flywheel mark. The flywheel is 225 mm in diameter. I calculate that if I measure 16.25 mm counterclockwise from the flywheel mark I should be at the stator mark. Again this involves way too many steps.

Re: Installing hpi mini rotor on a hobbit

Just got my hpi mini mounted on my hobbit Athena, no spark. All the wiring is right. I guess I have a question about the lines. I understand you have to line up the flywheel like with the middle big line in the stator. But at what position should the stator be in for that part. In the middle all the way to to right or to the left?

Re: Installing hpi mini rotor on a hobbit

oh my god this is probably the easiest thing you could ever set up.

Re: Installing hpi mini rotor on a hobbit

RADIUM CITY JO$HUA /

no spark means the wiring is wrong. check your grounds.

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