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3tj cdi differences/restrictions

Posted: Mon May 27, 2013 8:35 pm
by ibby4585
Not knowing much about the cdi's on these bikes I'm after some info.

Here's what I know.

The 4dx cdi is unrestricted.

The rrsp 3tj6 and 7 has a 3tj 82305-10 cdi which is restricted

The RR has 3tj BB7208 which is restricted

What I don't know

My racebike has 3tj- 82305-72 unsure what that means?

My UK spec rrsp has a blank cdi possibly a BDK unit?

Is there a difference in each cdi or are they just generic restricted or unrestricted

I know from experience the Tzr250's have several different cdi's units some with big performance gains ie Sugo, 00 cdi units on the 3ma.


Is the cdi the only restriction on these bikes?

Cheers
Kris

Re: 3tj cdi differences/restrictions

Posted: Mon May 27, 2013 9:27 pm
by Evilchicken0
I don't know much more than you about CDIs. The cdi controls the restriction.

Re: 3tj cdi differences/restrictions

Posted: Mon May 27, 2013 9:41 pm
by ibby4585
I've found this bit of info from BDK it mentions my race cdi (72) but refers to it as 'kit' I'm unsure what that means?

http://www.bdkraceeng.co.uk/Ignition.html

Re: 3tj cdi differences/restrictions

Posted: Mon May 27, 2013 10:22 pm
by hunter
When they use the word Kit they are referring to parts that would improve the performance of your machine for race use
hence race Kit,Yamaha would had supplied a box of performance parts that would have included the upgraded cdi


So the one on your race bike must be a kit one.

Re: 3tj cdi differences/restrictions

Posted: Mon May 27, 2013 10:26 pm
by ibby4585
hunter wrote:When they use the word Kit they are referring to parts that would improve the performance of your machine for race use
hence race Kit,Yamaha would had supplied a box of performance parts that would have included the upgraded cdi


So the one on your race bike must be a kit one.
Ahh right.

Cheers

Re: 3tj cdi differences/restrictions

Posted: Mon May 27, 2013 11:05 pm
by Evilchicken0
I thought Kit was a talking car ?

Re: 3tj cdi differences/restrictions

Posted: Mon Sep 09, 2013 2:11 pm
by maccas
Hi Guys,

I'm dredging up this thread!

Does anyone have any dyno printouts of the various different CDI's fitted and tested?

It's just it would be quite nice to know what is what.

From reading around so far it appears that what Kris wrote above is correct.

I have found that the rev limiter on the BB7208 unit is set at 14500 and the SUGO kit boxes (70,71 and 72) have the rev limiter set at 15400 (the SP has a lighter valve train and beefed up valve springs to cope with the higher revs.)

According to the kit manual the EXUP opening points in the 71 CDI are set to work with the optional EXUP exhaust that came in the race kit.

So if a 7208 unit is modified to make it 'KIT SPEC' will the exup valve opening/closing points be in the wrong place for the stock EXUP system?

I plan to do some back to backs on the dyno with an unmodified 7208 unit, a modified 7208 unit and a 4dx UK model unit to put this one to bed.

Any information anyone has to help this would be great! I assumed that 3tj info would be quite easy to find on the net. Apparently not haha. More is known about tzr250 3xv's and 3ma's and they are far less common than the 400's are. I'd love to find out what the Japanese tuning routes are.

Cheers,

Dan

Re: 3tj cdi differences/restrictions

Posted: Sun Sep 15, 2013 2:38 pm
by bendy3

Re: 3tj cdi differences/restrictions

Posted: Tue Sep 17, 2013 2:19 pm
by maccas
Hi mate,

Yep I'd read that one, definitely helped with some of the information so thank you :-)

I still need to do a back to back on the dyno with the various cdi's though otherwise it's all just hearsay and rumours sadly.

Cheers,

Dan

Re: 3tj cdi differences/restrictions

Posted: Tue Sep 17, 2013 6:47 pm
by rockTJ
Where in the world are you maccas?

Wouldn't mind putting mine on a dyno. Has race headers and BDK CDI box. Carbs are jetted to suit those and a race lump (my engine is bog std though afaik).

Does the BDK have a rev limit at all?? Only ask as I missed a gear last time I was out. I instinctively flashed a look at the rev counter and it was just over 16500 for a half a half a second :pray:

Chris