Race CDI system for GT/TR70 Suzuki's

[Kris Bernstein]

Odered a CDI unit from Elrectrix World in the UK today. Very tidy unit that bolts to the left or right side of the case. Since I will be eliminating the mechanical water pump on the motor and blocking off that side of the case,
the easy way to fit a self generating race ignition, was to use the alternator crank nose on the right side. Throw away the alternator and bolt up the CDI by drilling and tapping three holes in the case, at the casting bosses located at 120 degrees on the case.
The left and right sides of the case can be milled and narrowed to make the horizontal foot print of the motor barely 16 inches across. Skinny is nice.
Expect very little drag on the motor with only the Nova straight-cut primary gears and the stator magnet slowing the crank. Incidentally, the crank is one of Chris Applebee's "pork chop" items and is nearly six pounds lighter than the stock GT lump. The left side crank nose was cut off at the bearing face, so a blanking plate could be placed in the case, rather then the usual rubber seal.
http://www.electrexworld.co.uk/stk-235- ... 390-0.html

[Suzukidave]

It looks like a nice setup Kris . what is this going on

[diamondj]

Hey Kris,

Are you going to run a dry clutch on this one? I had thought the deal fell through with Nova for the run of dry clutches?

Jim

[tz375]

Kris,
That system looks like it uses HPI coils and stator and rotor with a new backing plate. Does it have the digital CDI's or is it analog?

Looks good.

I understand the electric waterpump idea, but I was confused by the reference to the right side of the motor - which is where the stock alternator goes.

Are you mounting it in place of the alternator or swapping crank end and putting it inside the left cover where the starter clutch etc used to be or inside a cut down points housing?

The few pics I've seen of your bike suggest an electronic ignition under the right (alternator) cover with a large battery to feed the beast.

[Kris Bernstein]

Initially we will run a Nova close ratio five speed with their straight cut primary gears. Ellis Moore at MPE has recently received the first set of castings for the dry clutch and has agreed to make the kits available on an individual basis to customers. We have several customers ready to purchase as engineering is completed and more casting come out of the foundry. Ellis plans on using the TZ350 clutch basket and it is Ellis' hypothesis that by using the more durable (and available) stintered bronze clutch plates, a 130 HP motor should not overwhelm the clutch.
HPI and Electrex World share many of their products and market specialty items each individually produce. In fact when I called HPI on the Analog CDI for the right side of the motor, they referred me to Electrex World for my particular application.
Yes, the CDI will go on the stock crank nose on the right side of the motor and the left side crank nose for the starter/water pump/points assembly will be cut off at the bearing face. After narrowing the cases flush with the crank seal boss, the only thing on the left side will be a blank plate to seal the crank case. The aluminum blanking plate will have sufficent room behind it to create a nice void for oil to feed behind (or to the outside) of the crank bearing(s) like the RD/TZ Yamaha's with the hole in the transfer pockets. Getting oil to feed the backside of the bearings via holes in the transfer pockets and primary compression requires some "porting" work on the cases, as well as, installing spacer washers IN PLACE OF the oil "slinger" plates on the crank shaft. With this work in place, all the SRIS tubes and oil pump go into the waste basket.
....and yet another horse power robbing mechanical gizmo is negated, much like the water pump...
Keep in mind (again) it is necessary to install the spacer washers on the crank during final assembly, instead of the slinger plates, in order to maintain correct dimensions.

Kris [/b]

[diamondj]

Initially we will run a Nova close ratio five speed with their straight cut primary gears. Ellis Moore at MPE has recently received the first set of castings for the dry clutch and has agreed to make the kits available on an individual basis to customers. We have several customers ready to purchase as engineering is completed and more casting come out of the foundry. Ellis plans on using the TZ350 clutch basket and it is Ellis' hypothesis that by using the more durable (and available) stintered bronze clutch plates, a 130 HP motor should not overwhelm the clutch.
Kris

Any chance Ellis will make a T500 version as well?

Jim

[Kris Bernstein]

Nova would be the better choice as they made quite a number of the dry clutch kits for the T500 as those motors are still very popular for the English Hill Climb cars. If you've ever seen the Zeeger's Yamaha Triple or the Sparton water cooled triple, based on the GT380. The dry clutches on all three bikes are very similar.
Contact Graham Dyson at Nova as I know he still has the molds for the T500 dry clutches.
When I was racing the T500 I used Nova's straight cut primaries and close ratio five speed box. Those old beasts are indestructible!

Kris