"Fly" redux: Super Fly! Bugeye 94cc liquid conversion.

[190mech]

Mar 22, 2022 8:22:44 GMT -5 fly said:

well I just wrote out a long post, accidently refreshed the page, and lost it all. 🤦

Long story short, had to cut down deck further than wanted to after router flub (forgetting to latch router base closed after seeing depth - not that bad, but still). So today I need to slap the crank in and cylinder and see where everything sits. I may need to order a thicker spacer.

I realized I *should not* use titanium as a spacer metal. It's too hard to be a abutting the aluminum cylinder skirt. It could potentially wear into the skirts with vibration, time.

I failed to make a reference point to mic how much I've actually taken off. I regret it SO MUCH. No idea how much I've taken off total now, must be closing in on 3mm, guessing 2.5-2.7mm.

Also was saying, if I could start again I would do a lot differently. may order a spare case set to start prepping if this setup isn't robust enough. would have just used JB Weld to smooth deck, been reading some hot rod guys use it to build up cylinder deck. would make bore a little tighter. would mill crankcase mating surfaces instead of JB experiment. although I'm still interested to see how that will work.

oh well, onwards.

Aluminum cuts like butter with sharp cutters,,I've under cut crap loads of projects due to this,just fab up an aluminum spacer to cover the mistake and get on with the project...

[fly]

Thanks 190, that's reassuring. I tend to hem and haw about issues I notice along the way.

Benji, I'm glad his posts here live on. He was always having worse and worse problems with joints and pain, as I recall maybe even his vision at one point. Whatever the case, as far as I'm concerned he's in the scoot tuning Hall of Fame. 

At any rate, this is fit with a 2mm spacer and *no base gasket*. So with a spacer with appropriate rtv top and bottom, and a bg with the same, hopefully that'll work out really nicely... if there's not too much space up top. I'll need to check squish but I'm hoping the crank and cylinder being tailor made for one another will mean it falls into place nicely.

So I'm gonna get started on painting, and if for some reason the spacer needs bigger, the 2.5mm ones should be here before too long.

[fly]

I measured the cylinder studs that came with the kit, the threads actually are 7mm on the dot. So I don't know why they seem so oversized when I try to insert them in the case. Thread pitch doesn't look diff. I guess I'll chase the threads and see what's up, I must have a 7mm tap or three around here. Or maybe just knocking down the apex of the thread. Like, they're not even a few hundreds of a mm off, they are 7.00mm and sharp.

[aeroxbud]

Normally a bolt thread is just under the size. So dead on 7mm it's probably too big.
A run through a die should sort it.

[fly]

Hot dang, that was *quick*. That's the 1mm one, they sent an extra 0.6mm one that looked like it had a little hiccup, so I have three. The 0.6mm are not flimsy at all, either. Those are 2024 vs 5052 for the 1mm
Pretty neat! 🤓

So I have some 2.5mm spacers as well. Rad. 

[fly]

I'm going to bore the case bolts to 8mm.

Here's why:

The stock setup let's the M6 bolts drop through the stator side with a lot of slack so they can pinch the trans side. They don't really do anything in terms of keeping the cases aligned. That's left entirely to the dowels, more or less (friction, as well). With this much an increase in forces, I don't like that. I want M8 bolts that line up, pinch, AND don't have that wiggle room they left with the 6mm bolts. That's six more spots preventing the shearing forces from screwing with the alignment and seal of the case halves.

There's plenty of meat for M8 bolts. I will close the cases aligned, and undo one at a time and pilot for 8mmm threads. I already have half a dozen 8.1mm drill bits I'll use to open up the stator side if an 8mm is too tight to allow the bolt collar to rotate.

I think the clear theme here is I want to do everything I can to bolster the cases for the 5-6-7x increase in power over stock. The roads here suck. I'll mitigate wherever I can.


ETA: I'm not gonna do the one above the boost/under the intake. That area is a little skinny for a M8 after trenching. All else are gtg, got Spec Bolt 8mm nickel coated 10.9's on the way.

[fly]

It's a substantial difference.

Well, that's 99% done. Those M8's are just Home Depot bought today to aid in the project, the spec bolt ones have a shoulder. I'm waiting to get those and mic em before I go ahead and drill out the stator side holes to nominal width. Right now both sides are threaded. I piloted and started the threads from the stator side, and then disassembled the case halves and cut the threads to full depth on the trans side. Worked great. Happy I did it. I'll throw up some pics of that all when I get the nickel ones and the small half drilled.

[repherence2]

Mar 24, 2022 15:33:29 GMT -5 fly said:

I measured the cylinder studs that came with the kit, the threads actually are 7mm on the dot. So I don't know why they seem so oversized when I try to insert them in the case. Thread pitch doesn't look diff. I guess I'll chase the threads and see what's up, I must have a 7mm tap or three around here. Or maybe just knocking down the apex of the thread. Like, they're not even a few hundreds of a mm off, they are 7.00mm and sharp.

those studs threads might be cut for class 5 (interference fit) or class 4 (close fit).  probably class five interference fit to keep the studs tight in the case and prevent them from backing out as well as preventing them from rotating when you torque the nuts.  they do that on certain applications where i work.  i have had to install/remove class 5 studs before at work as well as remove interference fit studs and tap to the holes to class 3.  and install studs with Loctite.  that is when i first saw a stud driver.

[fly]

Well, I ran a tap in the case holes and they fit fine -but close- now. So I guess class four sounds right. Never heard of that before, but have of interference threads. Interesting!

[fly]

Well, that's a lot of photos.

Anywho: spacer. I opted not to have them cut the holes. They can only cut line geometry that is half the thickness of the material. I could have made them a little bit bigger, but opted to drill them myself because nbd.

I ordered 2. This is where the first idea is at. It lines up nicely. I have started to relieve the underside in the areas that clip how the case is faced. however, the rear strands side has a very large lip. So I'm going to file them all down so that I don't have to sacrifice as much thickness. You can see where the reeds are. They're up enough to not interfere with anything. I'd say about 1/4"/6.5mm high of the boost. 

I'm not actually sure what is ideal for space there. If more space is ideal I have options. The big unknown for me is case volume. I don't know whether it would benefit from having more volume with a bigger spacer or not.

in other news, I have an OE subframe assembly coming. I'm going to attempt to modify it to allow for facing the carb rear.

[fly]

I want more space between the reeds and the cylinder, I think I need more volume. The reed cage doesn't block the boost. I just think I'm missing out on the whole point of 94 cc's if it's going to be too biased to top end. I haven't measured anything, but I'm pretty dang sure I need more intake volume than the smaller spacer provides. 

But I'm going to make it a two-piece spacer, so adjusting thickness will be easy. I just have to replace the non-angled piece. I'm going to be at least partially drawing up a plan for a intake cover, so I'll probably be placing a laser cutting order pretty soon. I'll have some non-angled spacers made in different sizes. I just pick which one works best and I'm good to go. Options! 

I also, just because I saw it when I was at the hardware store last week, picked up some sodium bisulfate. So I am going to mess with anodizing. The color scheme for this bike has been black and gray forever. It's kind of my general color scheme in life. 

But (minor) accent color 3, in spite of stage 6, I think would be orange. I was born on Halloween! And I like the colors. I've done some leather work where I dyed the leather black and saddle stitched with orange thread, it's just a killer combination. And then I type that and realize that I can make my own leather seat cover. I do need to address my seat. then the question is black with orange stitching or black with gray stitching. 😬

here I'm going to throw a photo or two up of the black and orange leather to solicit opinions:

huh I can't find a finished pic of that ax sheath. This build thread is the most I've ever documented any sort of personal project.



ETA: Re intake volume, especially with my intent to run taller gears.

[fly]

No, grey thread.

[aeroxbud]

I like the Orange thread. But then I like KTM. 😬

[fly]

I had started wet-sanding on a flat black coat on the cases. But I'm going to go wire brush it off, I decided to use alumahyde after all. the amount of work I've put into these cases at this point. 🤷 they don't have matte black in stock, so went with matte dark parkerized grey which should look pretty rad.

I'm still waiting on my GD nickel plated case bolts so I can start actual assembly. But the things appear to have been lost in transit. I get everything East of the Rockies without problem. But stuff coming from California seems to really be something the USPS struggles with, much to my chagrin.

[fly]

Okay this thing is just needing the very last bits of finishing. The base provides secure connection to case. I had to turn down the heads off some socket bolts, but it worked a trick. The angled second piece clamps to the base part with the reed valve, which is drilled/tapped at 6° to mach the angle. Lots of depth for those threads. I didn't have a bottoming tap so I drilled through and will use thread sealant just in case.

You can see I filed off most of the lips on the cases that interfered. The bottom plate is relieved to clear what's left. The top piece was obviously relieved because it was going to be used solo, but there's plenty mating surface. I will probably dress it up a little bit though. Relieve the whole perimeter and fit a superficial o-ring or something just for looks.

Got the nickel plated bolts, drilled out small side case, fits *awesome*. I need to open up one spot just a tiny bit to make sure the side of the bolt head isn't getting touched by the case.

Alumahyde paint should be here tomorrow! Non-stick graphite spray paint arrived today, going to do inside of small side and in trans housing and variator cover. Hope to make blowing belt and clutch dust easy. Doubtless the belt will wear it off some spots, don't care.

If I've not pulled these cases together by the end of the weekend somebody shoot me. Just need to finish evening out intake.

Then will get motor on a stand to reassemble. Then things should start moving. Probably going to start with a cut off kx85 intake. I have a new subframe assembly coming to try and mod to fit rear facing carb. But constructing that intake will need another job, and I wanna get this thing running before I spend a boodle of time working that out and making sure I can do the subframe right. I need to start looking at how that's done. I have to have it in hand to get an idea, really. Or see examples.