My 950 Refresh or Mission Creep...

Yea time for some more grease.

I was out at the shop yesterday squeaking away and we got a lot done. I have photos but a party last night at Revit left me a bit too intoxicated to properly post them up...

That's me on the right.

I'll do that tonight once I finish my shoot. Needless to say the results are impressive.

On another note I won't be making the rally (surprise!) Between the bike not being done (but soooooooo close) and me getting booked for the remainder of this week it's not happening. The good news is that I'm going to be leaving the bike with Chris until the chokes are resolved. I also want to be sure the 2wd is working and tested before I leave the proximity of the CNC.

Gregor

Did someone say chokes???

Chris hasn't made many updates but he has been making parts and progress. Thankfully I'm here in NYC for a few weeks and I got time over the weekend to head out to the shop to see the progress and help out a bit as we move from the endless jig making and fixturing to the actual laying down of welding bead.



These are the parts that will hold the gearbox in place at a perfectly square 90° to the headstock. One of the things I've learned from Chris is that making the part is the smallest part of the job. The design, the planning, the fixtures and jigs are what allows a part to be made and fit in what seems like an effortless perfection. There's a lot of work involved getting here.



He posted a shot of this but I think it's worth repeating in more detail. That is a perfect right angle fit with zero gap. You can't ask for more and I'm always learning from Chris. Nice.



To be sure that you don't warp anything you need to tack around the part without putting too much heat into it. Chris planned ahead for the thickness of the headstock by making sure the tube intersecting it was a similar thickness at the weld and also projected past the join. Smart detail.



Once the headstock tube was tacked a mock gearbox fixture, that aligned and attached to the major headstock fixture, was bolted in and the mounting brackets were attached to that. Again, it was a zero gap fit and the parts were tacked in spreading the heat to avoid any warping.



Between the jig and the engine it's some seriously awkward and tight out of position welds.



Once the gearbox mount was tacked Chris added more bead to the headstock while the jig was still on.



Then he turned some parts in the manual lathe so we could check fit.



And we mounted the actual gearbox and it fit perfectly.



Dead nuts perfect and square and it looks great. I'm getting pretty excited about this. Woody's should have my wheel finished and Chris only needs to make the long chain run housing and then we can begin to put this bitch together. And work on those chokes...

It's interesting to consider living with the 2WD on what is my main street bike. Portland has some rainy winter weather and I'm curious how it will work on wet pavement with street tires. It's going to be a learning curve and we plan on experimenting with the drive ratios but this is cool. I'm stoked.

Gregor

This is so cool...

So Very cool.....

Fan bloody tastic

Can't wait

But is it replicable cool?

I think Chris can answer to this more accurately than myself but the point of all of his jigs is to make this repeatable and consistent. The fact that Tony's frame and mine had a 2.5mm difference in width across the frame rails means that each frame will need to have the gearbox mounts fine fitted in house but he's built in adjustability to shim the gears accurately for the application. Much like a transmission the bevel gears need to be accurately shimmed for engagement.

Chris has done this entire project with an eye towards replicating the project on additional frames. We talked about it the other day and his estimate was that if he got a bare frame in he could do the entire process in 6 weeks now that my frame has served to establish the jigs and fixtures. Not a short time but a realistic winter project.

I think that Tony's frame will go quickly now that the bulk of the work has been done so that should provide a realistic time frame. As for cost - that's something that Chris can address but it's certainly not cheap. To me my 990 is a long term bike that I have a deep affinity for and I'm also a firm believer in the benefits of 2WD especially on bikes with excessive power to traction ratios. That paired with my desire for something different and a love of modification/improvements/customizing this was something that I couldn't resist. But, yes, to answer your question, it is certainly repeatable.

And don't worry about the chokes Pete (and the rest who are waiting) - we're both committed to getting that working. We've put too much effort in so far and I think it's the piece of the puzzle that makes the FCR's a no brainer upgrade.

Gregor

>>But is it replicable cool?

That's one of the reasons its taking so long! I originally planned on doing one, which can be done accurately in a quick and dirty manner, to doing 2, which makes a little investment into fixturing worthwhile. Then I had a couple of additional inquiries during the initial stages so thought putting a bunch more time into durable fixturing could be worthwhile. That added a lot more time but the plus is that it is now a 'process' and not just getting it all to fit.

Once we get Gregor and Tony's bike running I can get a handle on what the costs would be for additional conversions, hopefully in lots of 3 or so. The plan would be to send me a frame and forks and I send them back ready for reassembly. It would be a faster turnaround than these first 2 bikes (sorry guys!) since most of the legwork is already done.

As usual, keep checking on this thread for progress as the bike will be running this month.

Fantastic photos too !

Ok then, I start saving right now.

Same here.

And just when I thought my farkling list was completed... I better think again.

Was hoping to get some work done in the shop tonight but Chris has family plans and I've put in a long exhausting day at the studio so it will have to wait. At dinner last night Chris claimed that the bike would be finished "next week" but I'm not sure if that was the extra beer Gino sent over or just optimism. Either way I'm hopeful and I think Chris is dying to get this done as well.

Woody's called to say my wheel is done and they sent me a shot of Zach truing it up.



I still need to get another hub for my dirt wheel but this will get me started. Alright Chris, it's up to you to do the next post and I'll be back to test ride it in three weeks...

Gregor

Now that the headstock welding is done we get into the interesting part. Will the gears mesh nicely? Is there enough room to shim? Is Chris about to start looking for a new KTM frame?

In short, yes, yes, no!

This is the bevel drive input gear cartridge. It has 2 bearings side by side on the gear end and one bearing on the opposite end inside the shaft seal. The seal on the shaft and o-ring on the threaded connection will keep the inside nice and dirt-free.



I was able to keep making progress and finish welding the transfer case mount and the bevel drive input mount. Nice, low heat welds kept everything from warping too much.



One thing I have to do is grind a bit of additional clearance on the inside of the headstock.



I designed in some overlap in this welded joint to make it less prone to blowing out during welding. I ended up having about .02-.03" too much protrusion which kept the gears from being in proper alignment.

Once this was done it was pretty simple to get the gears in proper mesh.



Each output gear is independently mounted to the headstock so it was only a matter of machining each mount until proper mesh was achieved for each gear.



I'll now turn up one piece steel replacements for each mount. The area adjacent to the gear is now the inner race for a needle roller bearing so the stock aluminum material is no longer suitable. These needle bearings are crucial to keeping the gears in alignment under various front wheel loading and are a result of using the existing KTM headstock.

The positioning of the transfer case is perfect. The clutch driveshaft spins freely with no binding. I am very happy to get very good results in this stage of fabrication.

Now that I have the all-important position of the transfer case final it is a perfect time to finalize the chain housing CAD and start machining.



Hopefully Gregor will be able to make it here tomorrow and rebuild his forks with the Christini gearbox lowers. That will take care of the entire drivetrain forward of the transfer case which is the meat of the project.

Looks like my drunken schedule musings may not be too far off!

Damn, Gregor takes some nice pictures! (Obviously not in this post)

Gregor,

I'm working on a bicycle mount so I can ride down to Sisters for a MTB campout in late October. Seeing as you'll have your bike by then, maybe I should just make two?

So close. Can't wait to see it.

Once installed, does this make changing the head bearings a bit of a mission with getting the meshings right again?

>>Once installed, does this make changing the head bearings a bit of a mission with getting the meshings right again? Today 12:05 AM

Bearings are made with a precision in the .001" range so should be interchangeable without reshimming but I have not tested this out. The shims are 25mm ID and are available from McMaster in varying thicknesses. Also, the addition of the 2 large needle roller bearings will increase the life of the tapered bearings due to shared loading.