M Max

[rgvsp]

Any ideas why a 1990 GK76A would have a M Max derestriction box on it? I'm famaliar with them on two strokes. Generally people being cheap or not realizing they need a full power CDI will by them for two strokes. I'm not sure why a full power GSXR wouild have it on there. If it was a later model I could understand. Any ideas?

[CRM]

just to remove the 112mph limiter on the speedo. 4 strokes have them too, albeit a doddle to remove.
here is a curve ball for you totaly off topic. went to see another VJ23 last week, now its been a few years since i had a 23 (londonrs250 now has mine) and the CDI was the 00 one, thats the standard one isnt it ? it was an alleged genuine lucky strike, but i think not. just paint and still 40bhp

[Variablevalves suck]

Think the 00 is standard 40 hp model, tho dont know if they supplied a lucky strike. Looked at one of these way back and found them even more confussing than the gsxr with the different year changes etc. Was going for a RGV or NSR at the time but ended up with a NC23 and SDR200 for less.

[CRM]

yep thats what i recall too, there were 3 cdi's if i recall correctly, mine was either the 070 or 040 i cant remember, full power but retained the oil solenoid power feed for road use.
its alleged the genuine lucky strikes were full power. this one's been "fastlined" so take everything with a pinch of salt then

[Variablevalves suck]

Ye at least 3 maybe 4 Suzi boxes and then some kit stuff as well, i'd just sold a full power vj21 at the time and after reading about the trouble with restrictions on the vj23 and smart card nsr finally went over to a 400/4. The suzi is a sweet looking bike but must be a real hole in the head to get spares for.
Regards the M max box they plug into the gear sensor and then trick the cdi into thinking its in the lower gears giving full rpm in the higher gears. You can make your own using a resistor instead of the gear sensor.

[rgvsp]

Here is some CDI info I compiled for the RGV forum. I've spent years tracking down every 23 part imaginable and know the them pretty good. Pipes, CDI, jetting and sprocket will get you derestricted.

32900-42E00 Your restricted CDI
32900-42E10 Deresticted CDI that was made of the export V model. Runs your lights and oil pump
32900-42ESO Race CDI for unleaded fuel. I recently spoke with a 23 owner in CA and he found that this CDI runs his lights but he runs premix so I do not know if it will run the oil pump as well.
32900-42ERO Race CDI for high octane/avgas
0000A-9320-90s Autorimessa race CDI for unleaded fuel
0000A-9320-900 Autorimessa race CDI for high octane/avgas
0000A-9321-9SS Autorimessa derestricted road CDI. Will run your lights and pump. Not listed in any Autorimessa parts list I’ve found.
Sugaya R-2 Sugaya CDI for road use. Runs lights and oil pump. I’m sure Sugaya makes a race version as well but I don’t know its designation.
Programmable CDI I don’t know any of the specs but it was available at some point from Autorimessa. You can see it pictured on page 1 of the 23 kit parts and I’ve attached a picture.
From one I saw on yahoo auctions. I have no idea what software would be needed to use it.
One side note as well, it appears they were programming the 42E00 CDI’s at one point. My bike came with an extra 42E00 and when I installed it, it made the bike run as strong as with my derestricted Autorimessa CDI.

The confusion around 23's comes from the infamous "V" model. 99 percent of the 23's you will come across are T model's and restricted. Suzuki made a few hundred full power V models for export to Hong Kong. They make mid 60's stock. The easy way to spot one is a large id/info badge on the right side close to the headstock.

thanks for the info on the M Max!

[CRM]

good post, 010 it was i have a picture of it somewhere.
incidentally if your a regular on the rgv forum, you may remember ron from warrington ? rolls royce engineer ? he built a stunning 23 at a huge cost. we used to take both 23's out around wales for good blasts until i flogged mine, then the common RC30 took the fun out of it after that. anwyay we found those swarbricks worked better than the sugaya's in full power form and not only sounded deeper and crisper but looked better too.
He has said he would make another pair to order for £550 which i thought was good of him.
anyway here is a pic of my old 23

DSCF0044.jpg

[rgvsp]

Very nice! They are fun bikes. I enjoyed the hell out of rebuilding mine. It gave me the confidence to take on this basket case GSX-R400 now.

Here is my 23. It has the full Autorimessa race kit on it and 22 swimgarm to make it looks like the works RGV Noriyasu Numata rode.

[Variablevalves suck]

If you have a M max box it will have three wires. 1 is grounded and the others plug inbetween the gearsensor and loom wire.
If you take an ohm meter and measure the wires you will find that between the cdi side and ground you get a reading (usually 1.5k ohm). If you take areading between the sensor wire and ground for each gear you will get different resistances. The M max usually have a reading of around the second gear reading and you can make your own by using reistors the same as first or second gear etc that may/will give different advance curvers.
Never tried this on a dyno but usually make one using a 1.5K ohm resistor and get good results.

[Andy]

Just bought this(took a chance!) of e-bay do any of you fella`s know anything about it?
The title says;
RACING OFF LIMITER DERESTRICTER suzuki gsxr400 gk73 NEW . New in the packet with jap instructions only.... http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 0606851868

Andy