HPI ignition install

[4schizzle]

I been reading the posts on the "HPI CDI mini rotor ignition system for yamaha RD250, DS7, RD350, YR5, RD400" from treatland on this form as I am trying to figure out what CDI system to buy.  I have also been looking at the CDI systems available from Economy Cycle. I see alot of good reviews for the HPI system and it seems to be what i need. 

I am trying to piece together the 1975 RD350 I bought.  I am in the process of reassembling the motor as i replaced the crank seals and bored the cylinders. The bike i bought was basically a RD350 roller with a complete motor minus carbs, ignition, and wiring .  It was "half a roller" as it was also missing the front end. Front end installed thanks again to the forum!

I am curious as to what i will all need to run this system.  I building a race bike so i don't need any lights or battery, as i just need it to start and race!

I also read "Need schooling on Ignition options" so this is what I gathered.

I know that I need to run resistor boots or resistor plugs.   Do resistor boots come with the system?  From pic on the website it does not appear so. 

Do i need to buy the trail tech voltage regulator?   Not planning on running any lights.

I was planning on using a dirt bike style kill switch. 

Is there anything else i would need to buy to bring this RD to life?

Again thanks for all the help that the members of this forum have provided to me. 

[Striker1423]

Voltage regulation is a must as unregulated charging systems cook things.

[1976RD400C]

HPI makes an ignition for race bikes, no charging system, just spark.  https://www.hpi.be/item.php?item=068K089
If you want a charging system for lights then this one    https://www.hpi.be/item.php?item=210K176

[rd350mississauga]

Installation was fairly easy although the included installation manual was very helpful. Take out the existing generator (use the following video):
https://www.youtube.com/watch?v=RYW1hOxFfOQ

Once you remove the rotor and stator, you will find a small dovel pin which needs to removed with a plier, only then will the HPI stator install correctly aligned. I have attached the image (ITEM NO 14 in the image). Also remove the woodruff key in the crank as the HPI is a taper fit onto the crank.

The markings made by HPI on the rotor were correct, so i just needed to use a dial gauge to set the timing. Mine is set at 3mm BTDC. There are 2 separate set of markings on the HPI stator, so use the 2nd set of markings, when you consider that the crank/rotor motion is counter clockwise.

The stator connection goes to the CDI, then to the coils and then to the spark plugs. I use the original kill switch, but the polarities are reversed,  meaning ON IS OFF and OFF IS ON.  Iv seen some posts saying that using a relay will fix this but im ok, i can live with that, I call it theft deterrence (especially since im bad with electronics) 

Generally, i found that the bike was much easier to start with the HPI. Not sure about power difference since my bike is not a 100%. Leaks here and there that needs to be fixed first.

[4schizzle]

Installation was fairly easy although the included installation manual was very helpful. Take out the existing generator (use the following video):
https://www.youtube.com/watch?v=RYW1hOxFfOQ

Once you remove the rotor and stator, you will find a small dovel pin which needs to removed with a plier, only then will the HPI stator install correctly aligned. I have attached the image (ITEM NO 14 in the image). Also remove the woodruff key in the crank as the HPI is a taper fit onto the crank.

The markings made by HPI on the rotor were correct, so i just needed to use a dial gauge to set the timing. Mine is set at 3mm BTDC. There are 2 separate set of markings on the HPI stator, so use the 2nd set of markings, when you consider that the crank/rotor motion is counter clockwise.

The stator connection goes to the CDI, then to the coils and then to the spark plugs. I use the original kill switch, but the polarities are reversed,  meaning ON IS OFF and OFF IS ON.  Iv seen some posts saying that using a relay will fix this but im ok, i can live with that, I call it theft deterrence (especially since im bad with electronics) 

Generally, i found that the bike was much easier to start with the HPI. Not sure about power difference since my bike is not a 100%. Leaks here and there that needs to be fixed first.

Thanks for the responses rd350mississauga, Striker1423 and 1976RD400C.

I like the HPI system that can also power lights, cause i would like to have the option for lights if i decide to do something different with the bike. 

rd350mississauga are you running a battery on your bike?

Thanks again

[rd350mississauga]

I used to be getting 13.8V DC on my RR @2000rpm after ungrounding the coil lead, but not anymore. It's only giving out 5V @ 2000rpm now. I'm trying a bunch of stuff to find what's going wrong.

Others have successfully done it. Ill troubleshoot this summer and if there's still no luck, I'll be running the whole system AC.

[m in sc]

if you arent going to run any lights just ground the ac lead. it wont hurt anything. 

[4schizzle]

What spark plugs boots are recommend with the HPI ignition? I was planning on running either NGK  BR8HIX or BR8HS plugs, which i believe are both resistor plugs.  Do i still need to use resistor boots? 

[m in sc]

those are both resistor plugs,  run non resistor caps. If you cant find any, economy cycle carries them.

[SoCal250]

It's also possible to convert resistor caps to non-resistor by removing the resistor and replacing it with a piece of brass cut down to the same length. Hardware store brass screws (#10-24 or #10-32) can be used for this. This also permits easy switch back to resistor type if needed, as long as you save the parts.
(At least some NGK caps can be disassembled, not sure if that applies to all.)

[rd350mississauga]

What is the advantage of using non resistor type boot? Does it give better power?

I read on treatlands website that the HPI unit has to be used with resistor type spark plugs or boot, either one, else, it will burn the CDI unit. Im not really good with electronics. Please advise.

https://www.treatland.tv/HPI-CDI-mini-rotor-ignition-system-yamaha-RD350-p/hpi-yamaha-rd350-mini-rotor.htm

[rodneya]

The resistor only stops electrical interference that could mess with the CDI. On old cars not using a resistor plug or cap could make the radio reception go crazy.
No power difference, even if you have a resistor plug and boot.

[4schizzle]

Installation was fairly easy although the included installation manual was very helpful. Take out the existing generator (use the following video):
https://www.youtube.com/watch?v=RYW1hOxFfOQ

Once you remove the rotor and stator, you will find a small dovel pin which needs to removed with a plier, only then will the HPI stator install correctly aligned. I have attached the image (ITEM NO 14 in the image). Also remove the woodruff key in the crank as the HPI is a taper fit onto the crank.

The markings made by HPI on the rotor were correct, so i just needed to use a dial gauge to set the timing. Mine is set at 3mm BTDC. There are 2 separate set of markings on the HPI stator, so use the 2nd set of markings, when you consider that the crank/rotor motion is counter clockwise.

The stator connection goes to the CDI, then to the coils and then to the spark plugs. I use the original kill switch, but the polarities are reversed,  meaning ON IS OFF and OFF IS ON.  Iv seen some posts saying that using a relay will fix this but im ok, i can live with that, I call it theft deterrence (especially since im bad with electronics) 

Generally, i found that the bike was much easier to start with the HPI. Not sure about power difference since my bike is not a 100%. Leaks here and there that needs to be fixed first.

rd350mississauga from your reply the correct crank/rotor motion is counter clockwise. Correct? 

[Striker1423]

Yes, crank rotates counter-clockwise.

[rd350mississauga]

This one.