Recent Posts

Look into wintergreen oil and acetone to permanently soften old hardened rubber.

Works great, used it on a few bits on old corollas.

Well more progress

So it seems like the reed inlet on the RS Cylinder is a no go for a bigger reed block. I have a KX65 Vforce 3 block that will fit, but would like to put in something bigger. Unfortunately due to the external sizing, I can't hog it out big enough to take any decent reed blocks here.

The MX Cast cylinder will already accept one of the bigger reed blocks I have here, and also a GasGas TXT250 reed block, and probably would take a KX85 block. I may end up just using the cast iron cylinder, but it's sooooo heavy.

I have also made my stator plate and rewound it, I need to make some more holes in it tomorrow but it's ready as well.

Started with a Honda Dio Stator, I have tons of these. I turned the OD Down 1.5mm





Then I cut out a backing plate for the MX ignition pickup and the Dio backing. I also cut one of the poles off the plate to make room for the pickup.



Then I had to rewind the stator, it's fairly simple as it is single phase. Magnet wire and make sure you have the poles reversed every second one N/S/N/S in my case. This achieved by reversing the winding direction every pole. I have to tap the half wave in between two of the pairs of poles for my Regulator/Rectifier(Also off a Dio)



Other than I made the OD 1mm too big, It's a success. I will fix this problem and put thru holes for the wires in tomorrow and all done.

Here is an interesting turn of events.

So i did some cylinder rubs, the new "MX/DT" is pretty sad. Lots of casting flash and the exhaust port is nice and wide, but small. Nice domed piston though.

The RS though.. I mean from what I can measure from a service manual MarkT sent me, is pretty close to the good 73 MX cylinder... and the head has an Ok squish band as well.. But the RS uses a flat top piston, unlike both the old and new MX which from my research uses a domed piston. Also instead of having a small/large transfer setup, it has 2 of the same sized transfers.

So it seems like I already have an MX cylinder of sorts. Or something that can be modified to be one fairly easily

I have also found the rod, KTM 150sx, and using a prox bearing I can put the KX100 piston on there... will hopefully be on order soon from mongoose machine.





i will measure up the MX/DT cylinder next

That seems perfect. I will check it out when I get back from camping. If I can get a bearing to take up the extra mm on the small end it should work great.

Well I made some dummy bearings last night so I can install the crank and check the timings to see where I am at with what cylinders.

I also hate the head designs, there is no real squish band, just a big cascading dome. So the machinist in me wants to make a better head.

Rod/Stroke ratio ain't bad. I do need to replace the rod and bearing. I am currently trying to find a longer rod (110mm) that has a 28mm big end and 18mm small end. Then I could possibly use a KX100 Wiseco piston kit, which would also have the benefit of a lower compression height, but would require extensive cylinder modification to get the port timing back to normal.

Also going make a crank pin stuffer and possibly stuff the cutouts

Sounds good, there are basically brand new CST tires on them as well. If it paid for the typhoon wheel I bought I would be stoked.