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cdi modification

PostPosted: Tue Jul 01, 2008 11:32 pm
by chazman
I've been looking at the posts, haven't seen yet where to obtain a modified cdi for my skorpian. I'm in the northwestern U.S.
Also, who makes the best race bodywork?
Thanks,
Chaz

Re: cdi modification

PostPosted: Wed Jul 02, 2008 7:54 pm
by DAVID THOMPSON
use search box top right of screen

there are different yamaha boxes that will work
search for xtz szr and tdm
and see what you find
dave

Re: cdi modification

PostPosted: Wed Jul 02, 2008 8:44 pm
by iceman
who makes the best race bodywork?
That would be the Italians !
Image

Re: cdi modification

PostPosted: Wed Jul 02, 2008 11:51 pm
by Bill Jurgenson
as long as the engine is stock, you can use the TDM box. Its limiter ist set at 8400. But its drawback is the spark advance curve which goes to 40º, more than even the extreme 38ºof the XTZ box.
these boxes all work in the Skorpion. Both the XTZ and SZR boxes can be modified from the stock 7200 to 8400. I have modified the SZR box myself but not the XTZ which has a completely different circuit board.
OVER once offered a racing box with 5 different settings.
Slipstream tuning and Tunebike both modify the XTZ box.
You can ask Galen Miller at BikeWorx about box modifications.
In all cases concerning a modified Denso box, the advance curve is too extreme for very high compression ratios. 30º should be the limit for ratios above 10.5:1.
You are better off using a completely different ignition.
I suggest you try SPARKER TCIP4 standard from Ignitech.
ignitech_screenshot.jpg
ignitech_screenshot.jpg (43.63 KiB) Viewed 4976 times

You can program the CDI to suit your needs and it is plug and play as far as the connections are concerned.
I have no experience myself with this but several of my acquaintances do.
When I was still racing, I used first a PVL magneto, later changing to a SilentHektik triple spark constant loss battery ignition. Both worked fine but the SilentHektik started much more easily and had 16 different curves to choose from. The PVL had a an advance of 22º to which the static advance is added, usually 5º, making 27º total. I used the SilentHektik at 28º total advance. Neither can be used with the stock left side of the engine: flywheel and starter have to go. Back on the road and at the moment running a modified XTZ box, I can testify that the racing engine now vibrates much much worse than it did with 28º advance. I attribute this (and others in the know do as well) to the extreme 38º advance. I have not decided what to do yet, but I may get one of those SPARKER TCIP4 standard boxes as well. We'll see.

Body work?
there is really only one source in the states: Beasley. Listed with the Ducati fairings, scroll down to MuZ Skorpion.
In Europe there is MLB. This is what I use.
Image
(you can just see the crank stub with the ignition rotor thru the hole in the fairing.)
Many use modified to fit Honda RS250 fairings.
Slipstream is offering or knows where to go to get a complete racing set for the Skorpion based on the RS stuff which has a big airbox instead of the tank and the tank under the seat: look thru the gallery

Re: cdi modification

PostPosted: Sun Jul 06, 2008 10:05 pm
by hb1rd
I was wondering if the 660 raptor atv box would also work and what the rev limiter is set at on these units

Re: cdi modification

PostPosted: Tue Jul 15, 2008 3:36 pm
by handsomejackuk
i sem toremember a while ago thata trx 850, tdm 850 ignition box is the sam. i know it has two spark pulses but just use the one output and it rev's higher




Jak

Re: cdi modification

PostPosted: Tue Jul 15, 2008 11:39 pm
by Bill Jurgenson
TRX and TDM boxes are not the same. The TRX has 270º crank, the TDM a 360º crank.
See my posting further above: the TDM box is plug and play:
CDI_boxes.jpg
CDI_boxes.jpg (133.54 KiB) Viewed 4787 times

See also my comments on its use.
See also my comments in other postings about the tach issues involved in using a different box than that installed. (I hate having to continually rewrite...)
As for the Raptor box. AFAIK it is not plug and play. You can make it work when you know which pins are what and you connect it with individual shoes.
I do this anyway. I cannot see any advantage to using that OEM box, tho. One of the several aftermarket boxes offered in the states might be an option but not plug and play.
What do work is the box from the XT (3TB-82305-00-000). It could even be plug and play. And that of the SRX definitely works |9XL-85540-50-00) but not plug and play. It has no rev limiter at all.
But, as I wrote, the problem is, as soon as you raise the compression ratio, the spark advance curve. I though I had explained.
Get the IGNITECH box. It has all the advantages you can think of:
-it is definitely plug and play made, specifically for the xtz engine
-it is programmable, giving you any advance curve and any limiter you want
-it is cheaper
Cheaper if you buy it directly from them. The German firm KEDO is marketing a programmable plug and play box for 249€ which, although they do not admit, must be the same box.

Re: cdi modification

PostPosted: Wed Jul 16, 2008 1:28 am
by handsomejackuk
NO,

What i was saying was use one of the plug leads off the trx / tdm box it has a higher rpm ceiling than the baghira box. I know it has been done before because i read it somewhere else......


THanks



Jak

Re: cdi modification

PostPosted: Wed Jul 16, 2008 1:01 pm
by Bill Jurgenson
TRX and TDM boxes are not the same. The TRX has 270º crank, the TDM a 360º crank.


and

the TDM box is plug and play

Re: cdi modification

PostPosted: Wed Jul 16, 2008 3:07 pm
by handsomejackuk
later tdm has 270 deg crank but earlier tdm has 360 deg crank.
Jak

Re: cdi modification

PostPosted: Sun Apr 19, 2009 9:32 pm
by OLDMTNCARVER
I recently installed a set of rejetted carbs on my Baghira, I found that the engine would turn over but not run.
My stock 2001 Baghira, except for the after market exhaust, had not been run in a while so with a fresh charge on the battery (that held it's charge well, considering the abuse) I started by checking the basics.
First I checked for fuel and then spark, no spark. I tried another spark plug still no spark. I then checked the coil and coil assembly both as an assembly and as individual components. All were within their specifications.
With a friends help, we checked the fuses, wire connections, harness assemblies and switches finding nothing wrong.
The last consideration that I had was the CDI unit.
After reading other posts on this forum I decided to check how much a stock CDI would cost if it was the problem :shock:
After reading this thread I thought I'd ask for any other comments and experience since this thread, in the last year that might help.
Regards,
Robert