MZ/MuZ Riders

Just thought I'd post my experiences whilst fitting a TM34-B65 carb to my Skorpion.
Below are my initial observations

1/ The Throttle cable bracket is not aligned correctly with respect to the groove in the underside of the tank. The height of the
bracket is about the same. This means that I have to fabricate a new bracket which was expected. More info on this in a later post.

2/ The carb openings are as follows

TEIKEI

ENGINE SIDE 1 45.9mm AIRBOX 51.7mm
ENGINE SIDE 2 35.9mm AIRBOX 43.8mm

MIKUNI

ENGINE SIDE 1 45.9mm AIRBOX 54.8mm
ENGINE SIDE 2 39.9mm AIRBOX 54.8mm

As you can see there is only one diameter that is the same (green). This can be solved on the Airbox side (red) by fitting 2 off K & N pod filters from this page

http://www.knfilters.co.uk/search/univcone.aspx

I'm not sure which one yet but one with a flange inside diameter of 54mm (RC2340 to RC8090).

I'm not sure how the difference in sizes (blue) can be reconciled. I'm hoping that the rubber can be made to expand by 4mm without splitting or undue stress.
Has anyone fitted a pair of K and N filters and if so what are the part numbers?
I'm still working on the fabrication of a bracket as I don't have a welder and I dont want to chop part of the bracket off the Teikei and weld it on the Mikuni.
I am determined to get this to work as parts for the OEM carb are unobtanium (including service kits, float bowl gaskets etc).
Any tips or advice as always welcome.

David.

P.S Might have to buy a second 48mm hose (the right hand one that goes to the airbox) remove the smaller 40mm hose (left) and then cut the 48mm and 40mm in half (keeping the remainder half's as spares) and get a plastic/nylon reducer made up. I don't want to enlarge the smaller hole in the airbox unless I have to. Why are things never as simple as they seem?A 1 1/2 x 1 1/4 concentric butt weld reducer would be ok (48.3mm to 42.2mm) or something similar in nylon.

Interesting. Please keep us posted. I want to do this with my Baghira but i'm postponing it because too many other things to do and i know it'll turn out to be not so simple.

I wonder if rubber connectors couldn't be made from some coolant hose. Although I suppose it might be a mission to try to find pieces that have the right diameters. But maybe it's stretchier than the carb rubbers.

You can cut and re-weld the bracket on the carb easily to make it fit under the tank.

There is a picture of how the end result looks on my bike in this thread.
viewtopic.php?f=3&t=3536

Cutting a bigger hole in the airbox for another stock intake rubber works perfectly if you are up for it. Myself I just used some K&N pods that came with the carb courtesy of the previuos owner.

BTW servicing kits for the carb are not unobtainium as the stock carb is basically identical to any Yamaha 660 5-valve XTZ/SZR or even an old 600 XT/TT.

Received my Mikuni's yesterday from KEDO. Bought them without rejetting, just ordered it with extra main jets 115 - 135 in steps of ..5, also two idle jets 17,5 and 22,5.

The necessary ring for the right carb was using the flange of the old cv carb. Cut it of and used a 40mm drill to get the inside diameter right.

The cable mount is made just by rotating it about 45 degrees, therefore two new holes were made and some cutting to get some space around this screw mount in front. The large truss in front is shifted to the left position. The cable holder even has a small bulb right where it shoul be for the new hole. What surprises me is that no one seems to turn the "cable wheel" as well, although a proper alignment along the radius is only possible if the cables and cable wheel maintain their relative position. So i drilled new holes to mount the wheel about 45 degrees shifted. Afterwards the idle screw was shortened for some necessary headroom under the skorpion tank.



Furthermore i installed two K&N RU 1780 filters. They are huge!


They have 52mm flanges, but fit easily around the 54.8mm carbs. The long flanges also form some kind of a velocity stack. What effect it will give is guessing, a dynorun is planned after fitting a high comp piston and flowing. We'll see.

Hopefully I get the chance for some proper testing this weekend, it's getting cold and rainy overhere!

Hi,
Can you post a few more pictures of the cable bracket from different angles. I just want to see how the the bracket has been modified from original. How did you change the aluminium bracket/rail that holds the two carbs together? Do you still have enough room for the choke lever to work?

Thanks.

The rail in front of the two carbs can be shifted between two positions when unscrewing the four bolts completely. This is necessary for repositioning the bracket. The rail doesn't need cutting or welding because it isn't part of the repositioned cable holder.



Tomorrow I will take some pictures, but i can already tell you there is no space for the original choke lever.

As promised some pictures:





Also made a 1.0 version of a choke control using the original lever and cable. I found some parts of an old Dellorto carb which are bolted onto the right carb choke. Made to be functional, the next version will look better.

Hi guys,

Funny that I am trying the same installation right now, posted here in the tech talk board. I like the ideas presented here, especially the choke cable. But I'm waiting to hear how your fuel tank(s) fit...I had to move the cable holder as far as possible to the right before the tank would even think about dropping into place. I even took off a bit of the connector bracket, screw, and the boss it screws into. And since I want to use the airbox, I've ordered jets down to #90...

zippy49 wrote:Hi guys,

Funny that I am trying the same installation right now, posted here in the tech talk board. I like the ideas presented here, especially the choke cable. But I'm waiting to hear how your fuel tank(s) fit...I had to move the cable holder as far as possible to the right before the tank would even think about dropping into place. I even took off a bit of the connector bracket, screw, and the boss it screws into. And since I want to use the airbox, I've ordered jets down to #90...

Tom in SoCal

What price did you pick up your carbs for? The price that Vintage Spoke quoted me was something like half of what KEDO charges for them.

Thanks

zippy49 wrote:Hi guys,

Funny that I am trying the same installation right now, posted here in the tech talk board. I like the ideas presented here, especially the choke cable. But I'm waiting to hear how your fuel tank(s) fit...I had to move the cable holder as far as possible to the right before the tank would even think about dropping into place. I even took off a bit of the connector bracket, screw, and the boss it screws into. And since I want to use the airbox, I've ordered jets down to #90...

Tom in SoCal

Here a picture of the tight space beside/under the tank:



Not a lot of room, gently dropping the tank pushes the carb a little sideways when the petcock hits the frame. Doesn't do any damage though. When the tank is fully seated there isn't any interference. The cable bracket zippy49 uses sits higher, therefore hits the slanted side of the tank (this sump thingy).

Lowering the bracket meant the choke knob had to be removed completely,the rod has been cut as short as possible to get enough stroke. I even bent the levers pulling the chokes to gain some extra. Yesterday the proof of the pudding, starting quite easily at 3 degrees C./40 deg F.

Hi edf, they were a lot of money, and Kedo will not sell directly to the USA. I checked the latest Kedo price, and Vintage gets that plus shipping and some profit. Sorry but I am reluctant to admit the exact amount!

Meanwhile, I am going to get my welder to make a nice battery holder...using a Shorai Li-Po now. Those big K&Ns look better all the time...used them on two SRs and an SRX.

Cheers, Tom

edfmaniac wrote:

zippy49 wrote:Hi guys,

Funny that I am trying the same installation right now, posted here in the tech talk board. I like the ideas presented here, especially the choke cable. But I'm waiting to hear how your fuel tank(s) fit...I had to move the cable holder as far as possible to the right before the tank would even think about dropping into place. I even took off a bit of the connector bracket, screw, and the boss it screws into. And since I want to use the airbox, I've ordered jets down to #90...

Tom in SoCal

What price did you pick up your carbs for? The price that Vintage Spoke quoted me was something like half of what KEDO charges for them.

Thanks

Kedo has a distributor in the US. I've talked to him before and got a quote that was Kedo's list price plus the usual in country shipping. I'm guessing he makes his money on whatever discount Kedo gives to their distributors.

Thanks

Hi Hajok,

My bracket is only about 1/4 inch higher, does not hit the bottom of the tank, so I think the difference is due to "manufacturing tolerances." It is a rotomolded plastic tank after all. And there is not much "opening" cable left on that pulley, either way.

As for jetting, I am working on Plan B, and have ordered the K&N 1780s. I don't think that the stock filter will handle the airflow, even if the paper is replaced with a layer of foam or gauze. I am trying just the (SS?) screen in the old airfilter frame for now.

Now for the big question. Has anyone managed to remove the airbox without unbolting the subframe? The wiring harness next to the petcock is already pretty hammered from all the tank R&R, can I get it out toward the front once the carbs (and boots if needed) are removed?

Tom in SoCal

Hajok wrote:

zippy49 wrote:Hi guys,

Funny that I am trying the same installation right now, posted here in the tech talk board. I like the ideas presented here, especially the choke cable. But I'm waiting to hear how your fuel tank(s) fit...I had to move the cable holder as far as possible to the right before the tank would even think about dropping into place. I even took off a bit of the connector bracket, screw, and the boss it screws into. And since I want to use the airbox, I've ordered jets down to #90...

Tom in SoCal

Here a picture of the tight space beside/under the tank:

image.jpg

Not a lot of room, gently dropping the tank pushes the carb a little sideways when the petcock hits the frame. Doesn't do any damage though. When the tank is fully seated there isn't any interference. The cable bracket zippy49 uses sits higher, therefore hits the slanted side of the tank (this sump thingy).

Lowering the bracket meant the choke knob had to be removed completely,the rod has been cut as short as possible to get enough stroke. I even bent the levers pulling the chokes to gain some extra. Yesterday the proof of the pudding, starting quite easily at 3 degrees C./40 deg F.

I should have a pair of carbs on the way soon. If my eye is any good, I won't have to do any throttle cable mods to clear the '93 Suzuki RG125 tank that is going on my Skorpion.

Nevermind. Due to some confusion, the price went up and exceeded my motorcycle budget for the next few months.