Cobra CX65 Mini Moto

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The Spokes have arrived!!

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Ed had some take off PMTs for the Cobra. We are getting closer folks! The nice thing about these tires is that thanks to Alex there are no chicken strips.

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There is some late night Cobra action going on at Ed’s place.

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The Cobra project is really coming along swimmingly. Ed has been diligently going at it, and I am super grateful for the help. It’s kind of like Santa’s workshop for bikes.

So that the wider rear tires can be fit the swing arm must be modified.


Another nice feature to add are slider spools. This keeps the tracks happy (they want to see sliders on everything), and it makes it much easier to work on the bike via a stand.

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It’s a little bit tight in there! Ed says that if we change the gearing a little to a 14 or 15 up front, and a 45 in the rear it should loosen things up a bit.

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It’s pretty much ready to go. There are a few more little things like bar protectors, and new grips, but for the most part it is ready to come off the table as Ed says!

I seem to have misplaced the radiator guard. Hopefully it was put in a Senda box, and can be found. I expect that I’ll have to order one from Cobra. That’s okay though as I bought all new plastic parts for it so a new guard seems appropriate too.


I’m super excited about this advancement. This poor bike hasn’t run in year with no fault of its own, and now thanks to Ed awesome help we should be getting it out to Sonoma, Dixon, and Stockton this and next month. And of course in June out to GPR Camp 4!!

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We made it out to the track at Dixon yesterday. It was an incredibly nice day for it too. I got quite a number of shots which I’ll be posting in the Track Report section. But I didn’t get to ride for two reasons. One the bike wasn’t ready, and I forgot my boots!

I did work on the bike, and made some progress, but we didn’t have the right tools, and resources to make it happen. Still the Cobra is getting closer and closer. I did get to ride it around the parking lot a bit, and I can tell I’m really going to be enjoying this bike.


Since I didn’t have my boots I conscripted Alex to be my test rider. Since he’s been racing a Cobra for a couple of seasons now he was the perfect choice. I told him, this bike hasn’t been running for over three years now so just start out in the parking lot, and check things out. He came back stating that it didn’t have any brakes. I check it out, and sure enough they weren’t stopping the bike. Ed did’t believe it so he had a go too. I think he just wanted to ride a two stroke again.


Both Ed and I suspected glazed pads since it did slow the bike down, just not enough. I pulled the caliper off and inspected it.


I pulled the pads and sure enough they were glazed. Cleaned them out, tested the bike and still the same.


I suspected that the disc was glazed too so I worked on it, but still the same results.


I then checked out the master, there was resistance, but it actually would go all the way to the stop. The controls are tiny dirt bike style so neither of us could tell at first, but with inspection it was obvious. We also noticed that the clutch master was leaking. So the bike needs some hydraulic overhauling.

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Today was a white bike day. Both the Cobra and the Panigale enjoyed some much needed refreshening of the hydraulic fluids. For the 899 things went fairly well, although I didn’t get to the rear brake. However for the Cobra it seems it didn’t go so well, because the front master must need a rebuild. It’s not building enough pressure.


A little before and after action. It is still difficult to tell from this photo, but I did a lot of cleaning on the both bikes today. No photos of the cleaned up 899, but the Cobra needed a lot, and even though it got a lot of cleaning, there’s going to be more in the future as I ran out of the Simple Green.


First it was cleaning time. This took a lot longer than expected as there was a lot of grime on the bike from the previous owner. Thankfully Simple Green cuts right through that crap. I actually use one bottle of Simple Green, and empty Simple Green bottle filled with water, and a tooth brush. It’s an arduous process, but the results are great. If I had some WD40, and a soft cloth I’d have the full Bill Wallace technique down.


To work on the front master the throttle needs to be moved out of the way. The. reservoir cover was very difficult to remove, and required a fair amount of persuasion. The fluid in the reservoir was totally black. First I cleaned it out, then filled it up with fresh fluid.

It took a lot of work on this master to get it so that the res would be clear after some bleeding. Probably because pressure wasn’t getting through.

This made the process futile, and even though I pumped this lever a whole lot this afternoon, it was all for not, and the master is going to have to be reworked.
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The clutch was a little bit easier. Like the brake the cover was difficult to remove, but not quite as much.


The rear brake went much better. Bled out the old fluid, and it came up to pressure very quickly. I should note, I don’t run the nasty fluid in the res through the system. I first use a paper towel, or napkin to suck out the old fluid, and then clean the res.


And that was basically all I could get done on the Cobra today. I noticed yesterday that the float valve in the carb is leaking. That’s probably going to need to be replaced. The front master will either need a rebuild, and possibly a replacement. Have to inspect it to find out. I also need to replace the grips and get the bar protectors installed. There’s still a lot to achieve, and very little time in which to do get things done.

With the two bikes together it’s interesting to note that the seat height is very close, the peg hight is very close, and the Cobra’s bars are higher.

While it is exceedingly disappointing that progress is going so slow on the Cobra I can tell this is going to be a very fun bike to ride.

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Today was attempt to solve the front master issue. It went fairly well until it didn’t.


The first step was to remove the system from the bike. The master employs a pair of standard 8mm head bolts, and the caliper a pair of 6mm head socket caps.


Once off the bike a bit of cleaning was in order. Getting dirt in the system could cause a catastrophic failure down the line. Removing the clip was rather difficult. I had to extend the fingers on the tool to their farthest extension, and even then it took a bit of finesse. Once out the rest of it came apart easily enough.


Once opened up it cleaning the cylinder was in order. Then flushing it real well with brake fluid to remove any dihydrogen monoxide that managed to remain.


The show stopper was realizing that the revision kit was for a different master. ざんでしたねえ。


I was able to look up the proper fasteners for the fork guards—M6x16mm, and fortunately I had some in the stash from the last Bolt Depot order!

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After realizing that the master was the reason why the brakes were disabled it didn’t seem like it would be all that difficult to master.


While I’ve ordered some replacement parts Ed found a rebuild kit in his spares so that the bike could get put together sooner.

Comparing the old parts with the new parts it is clear to see that Cobra has updated the internals. They have moved from a metal rod to a plastic one. Not having actually used the metal one I can’t actually compare the performance difference, but it is interesting to note that they stopped using a screw spiral design too.

It’s worth noting that the two seals are actually different. The one near the spring has indentations around the lip of the smaller end. It can be seen in these photos, but just barely. I should have taken better photos.


With things cleaned up, the pump primed, the parts went together easily enough. The difference in feel was quite obvious—there would be pressure!


Once on the bike I did another bleed to gain more pressure, and a little test ride. The brakes are now working, but it seems like they should be better. I have ordered new seals for the caliper. When they show up with the other parts it will be time to see if that helps. At least for now the caliper doesn’t appear to be leaking.


With the brakes functioning again it was time to move on to other aspects. The fork protectors were easy enough to install. I also then started looking into adjusting the shock. Upon removal of the seat I discovered more stuff to clean up. Then it was time to pack it up again. The shock will have to wait for another day. The good news is that the bikes is getting there!