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very nice work. as an engineer with actual machining experience, both cnc and manual, and doing 3d cad work daily, you work looks fantastic. Very nice, has to be satisfying to get this far along. the frame looks really great too. (i have a custom framed road bike i did as well, its time consuming but worth it). keep up the good work.
 

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very nice work. as an engineer with actual machining experience, both cnc and manual, and doing 3d cad work daily, you work looks fantastic. Very nice, has to be satisfying to get this far along. the frame looks really great too. (i have a custom framed road bike i did as well, its time consuming but worth it). keep up the good work.
 

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Discussion Starter #23
Thank you for the encouraging words. If I was closer to anyone here, I'd like hanging around building stupid/crazy stuff. Still debating moving back towards St. Louis, MO (actually the Illinois side) to be able to hang out with my brother and build stupid stuff with all my tools. "Hey, we have this engine, what can we put it in?"

But anyway, fixed the gear box bearings in the lathe and made a few more parts. I went with the idea for the swingarm pivot and ran with it. So, the larger cups will get welded into the frame. Smaller one on the chain side, larger threaded one on the brake caliper side. Sleeve threads in from the inside of the frame. Once I build the swingarm, the sleeve will add preload to the thrust bearings, the jam nut will hold it in place. Cups are 6061 aluminum like the frame, sleeve and jam nut are mild steel. I'm also building a hollow shaft that will interlock with the tabs on the sleeve, and use a standard nut on the brake caliper side.

Because I sometimes make my own tools at this point, I have cold blue compound, so I'll likely just "blue" the sleeve and nut.

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Discussion Starter #24 (Edited)
Okay, sorry for the delay. Had a week with lots of extra physical therapy. Since I didn't get back to work yet, I went to St. Louis to visit family for Christmas. And I've just gotten over the cold I got while there. :( But, I made some progress during that time period anyway.

1st things first, I made some progress on the frame. Got it welded/tacked enough to set it up with a rag jammed around the steering stem in place of bearings, just to get a rough idea of how the size is working out in real life .vs paper. Seems about perfect, as my head ends up just over the steering stem, as opposed to the pocket bike where my head is over the front fairing when leaning forward. I also got those swingarm mounts welded in. I still have gussets to add around the headstock area, and cross members for engine mounting tabs and shock mount, tabs for mounting a rear subframe, tabs for mounting rearsets and an oil cooler. But the main basic shape is there. And to boot, with just the headstock and bottom cross member welded, the thing is super stiff.
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Then, just so I could take some parts out to show family when visiting, I also whipped up the lower triple tree. I still have finish work on the upper and lower triple before getting anything anodized, but here's the final product so far.
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In case you're wondering, I did make the stem a little longer on the bottom on purpose. I intend to make a front stand that will go in the bottom of the hollow stem. Because of that, I didn't want to be able to accidentally damage the threads. I'm still thinking about boring the center out to 7/16's instead of the 3/8's it is now. I'm also considering boring the bottom 1/2" slightly larger, and then making a steel bushing to press into the bottom end just to put up with the front stand pin better than aluminum would.

Question time now though. I'm going to go ahead and order the pmt slicks. One of the next things I need to make is the swingarm, and before I'm done with it, I'll want to mount the front and rear wheels, and jack the frame up to where I want it to position the shock mounts. I got the 2014 wheels as suggested. I've noticed the PMT slicks for the rear come in 120 and 130. I think the 130 was added for the grom sized rear wheels? Is 130 the better profile for racing? I figured I'd go with medium compound.

2nd question. I think I may go ahead and order the fork kit while I'm at it, so that when I have a rolling chassis, it's actually the fully prepared suspension. So, Ohlins or Racingbros? I'm leaning towards Racingbros due to the adjustability. The only thing I don't like is that the Ohlins just comes with two sets of springs, but I need to guess for the Racingbros. I'm right at 190. This bike should be lighter than grom, but slightly steeper fork angle and higher speeds/braking forces. I've been pretty good at modifying the suspension on every bike I have so far, including cutting springs down, closing the coils again and grinding flat, and making spacers to up the spring rate, so I'm kind of inclined to get the springs for riders up to 195, instead of the springs for riders from 190-285 pounds. But if anyone has direct experience with Racingbros springs, I'd love to hear it. Thank you!

One last thing, I am finally cleared to go back to work starting Monday. That means I can start affording more of the parts! Yay! But, that also means I won't make progress as fast. Don't be dismayed. I will continue to update as I make progress, and I'm committed to trying to get this thing running by this spring. I've been researching working with fiberglass and carbon fiber while sick. I'm also going to be ordering the Daytona 190cc motor to make those mounts as well. Cheers!
 

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I have Ohlins with one spring from each set because I weigh 200lbs, which was right in between the two spring rates. Spring rate feels spot on. Using Ohlin's 5wt fork oil, it feels over dampened for the street. I'm sure it would be perfect on a nice smooth track.

I installed the Racingbro's fork kit on a buddy's Grom. The Ohlin's 5wt fork oil is def too light, however the compression/rebound adjustments actually do work because I can feel the forks tighten/loosen up. There is also spring pre-load adjustment which is nice. The only thing you need to watch for during the install is to not bind up the rebound/compression adjustment rod when you are screwing down the fork caps. Sorry, I forget which spring rate my buddy ordered.
 

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Discussion Starter #26 (Edited)
Don't have picks to post up (I have a couple on my phone, just being lazy about uploading them), but thought I'd update anyway. I've gotten started on a few bits for the swingarm. I made the pieces to press the bearings into for the front, have the rear axle adjuster pieces in the back made, but I'm going to trim down the material that doesn't need to be there. I have the front pieces welded to the tubing for the swingarm, but still need to start making bends to get the shape. For that, I've been waiting for tires that I ordered just over 3 weeks ago. Ordered PMT slicks from Drow sports, and they still haven't even shipped yet. Kind of fed up with waiting at this point, and I may not order these tires from them again (Disclaimer, I have received excellent service from them on stuff they have in stock. Their site does say there can be extra shipping time for these tires. My issue is that they never contacted me to let me know it was going to take more than double that lead time, AND their site said the tires were in stock. Over a month to get tires during race season would blow a lot of the season. But like I said, they've been great otherwise.) I've even started looking for other places to order them from just to get my first set of tires.

I have gotten a few more parts in otherwise. I got a 4 piston brembo caliper, caliper mount, and a Kitaco full floating front rotor, ordered from Japan after I ordered the tires. I chose the Brembo P4 30/34 piston because I can find my favorite brake pads for that caliper. I haven't found them for any of the other alternatives for the grom. The Vesrah JL compound pads. The hotter they get, the better they grip. I've also ordered and received the Daytona Anima 190cc engine and carb. I have a 125ml oil cooler on the way. I have the Racing Bros fork kit. I posted in the fork mod thread about those. Because of the external valving adjusters, the dampening rods attach to the fork caps differently, so there's no easy way to lengthen the dampening rods. That said, I still have to measure the stock rods (I'll be measuring to the part of the fork cap that mates with the fork tube) to see if they are already lengthened. If not, I've decided that I'm going to make then longer anyway. The rods unthread from the valves at the bottoms, and are made out of 12mm polished rod, and the adjuster rods are just 4mm aluminum with a hex cut on each end. Pretty simple stuff since I have the machines. I already made the special tool for holding the fork tubes in the vise. I'm about ready to get the welder out of my way, actually mount my vise on the workbench in my basement (not nearly as much contamination potential as on the bench in the machine shop garage), and start disassembling the forks.

I've also welded a little bit of reinforcement on the frame at the headstock, as well as a tab for possibly mounting a fairing stay to the front, and a tab for a steering stop. As soon as I get done with the forks, I'll be ready to press on/in bearings and races and actually mount the forks. Once I get the tires and make the swingarm, I'll set the almost rolling frame up with a jack under the bottom of the frame, set the appropriate height/fork angle/swingarm angle and make the shock mount. Once done with that, I'll work on mounting the engine. That's the plan anyway. After that, I need to make something for mounting the oil cooler, the rear subframe, and a fuel tank/fuel cell. Still undecided on if I'll weld up an aluminum tank, or find a pre-made fuel tank/cell that will work. Either way, it'll be something hidden under a tank cover, simply for the fact that I'll be racing this thing, so I don't want a tank that'll risk damage from crashing.

If anyone knows of a fuel tank or fuel cell that would potentially work, let me know. I've tried looking for generic tanks, and haven't found much.
 

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Discussion Starter #27 (Edited)
It's just after 6am, I'm really tired, about to go to bed so I'm ready for my 12 hour shift that starts at 5pm. But, I needed to post. First, I modified my statement above regarding Drow Sports. I think I was rightly frustrated with how long it took to ship my tires, but they have been great with everything else.

Second, I've made some good progress since I got the tires. I have more pics from the process of getting it to this point, but like I said, I'm tired. So here is how the project sits now.





And lastly, the engine just hastily placed on some scrap pieces of I-beam. Not at the right height (too high by at least an inch), but just to get an idea.
 

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for some reason can't see any picture attachment with the 3 you posted above. If you use pic that are 1280x1280 size max and .jpg extention and use the 3rd icon above from the right and click it, it will ask if you want to post "basic uploader" choose from "computer" choose your photo and click "upload"
 

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Discussion Starter #29
A few more updates. Work has been hectic with installing a new 3 stage 6 cylinder high pressure air compressor, blow molder, conveyor/bagger/palletizer system, and a stretch wrapper. Still, I've gotten more work in. For starters, I reinforced the swingarm and where the upper shock mount is between the frame.





I also made a chain slider that wraps around the front left portion near the front sprocket. Used UHMW plastic, a strip 1" x 1/4", heated up and bent the shape, let it cool. Don't have a pic though.

I took it in to work to weight it on the pallet scale and rode it around the lot for testing a bit. The rear spring is still just a little soft, so I have a new one already. As it was though, it handled really well! Drug my knee wearing regular cargo pants. It usually takes me a little while to work up to dragging knee. On this bike, I still felt like I was being conservative, and ended up getting to the edges of the front tire. It just felt stable everywhere except for when I tried to wheelie it. LOL Anyway, as it sits in this pic with a temporary exhaust and small plastic pocket bike gas tank with 3/4 gallon of gas, it weighed 157 pounds. I thought it was lighter, so I guess I'm doing really well with my shoulder since the surgery!



And finally, I've started roughing out the shape for the tank and tail anyway.






I'm still roughing out the shape of the tank and the tail. I've tried tig welding exhaust tubing, and had no luck. Got it fused together, got the outside looking not too bad, but the amount of weld sagging into the interior was unacceptable. I think I'd need to pressurize the tube with argon to prevent the sagging and such, and that's just more work/expense/gas than I'm willing to expend. So, I made a tube bending die on my lathe, and I'm preparing to bend an exhaust out of a single length of 1 3/16" stainless thin wall tubing.

I'll eventually get there, but I'm very happy with how this thing rides so far. The extended Racing Bros cartridge kits in the forks with the spring choice work fantastic. The R6 shock with separate high speed compression, low speed compression, and rebound adjustments seems very good after I pulled it apart, changed out the preload adjuster for the threaded type, added a schrader valve, new oil, and recharged it with nitrogen. Front brake works really well. Love that big Brembo 4 piston with the floating rotor. Also, I know this changes with weight compressing the suspension in a turn, but with where I have the foot pegs mounted for now, I can lay the bike over till the clip-ons are only about 3" from the ground before the foot peg hits.

Cheers!
 

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Discussion Starter #31
I'm finally getting another chance to start working on this thing again. My last job kept getting in my way and switching me to 12 hour overnight shifts, so I found a dayshift job that allows me to do 4 10's and have a fri-sun weekend as standard.

Anyway, in my last testing, I tried some Mitas medium compound tires. I kind of shredded the tires. In retrospect, I think it was maybe a little too cool of a day for the compound to work properly. It was a high in the low 60's that day, around 20 psi cold. Oh, and I finally made a permanent exhaust. The thing taped on the tail is a GPS lap timer (more details about a better solution to this too).





As for new changes to try this spring. Well, first off, though I could ride it effectively, my friend was right that it felt like it was a little twitchy. Well, I made the triple trees adjustable, so I made some new inserts. I prepped making two sets of inserts, and only finished one set for now. I made them 2mm offset. I figured I could try those, and then see if the next set should be 1mm, or 3mm, or 4mm. But, in the name of keeping turn in, and keeping things stable, I also made a mount for a GPR steering stabilizer. My intention is to try the inserts first, see which gives the best balance. If more stable makes the turn in too slow, then I can go back to other inserts and try the stabilizer.





The 190 Daytona, due to clutch/transmission issues really requires the use of the clutch on upshifts. For racing, I'm used to just preloading the shifter and blipping the throttle. Word on the street is that the slipper clutch fixes this issue. If not, then my back-up plan is to tear the motor down for inspection anyway, and then maybe undercut the dogs on the gears that interlock for engagement anyway. But, here it is.



One other performance related issue ... engine power. With the new exhaust I made, the engine flows a LOT better. Because of previous experience in porting heads on a supermoto for racing in several stages, I'm familiar with the intake/exhaust power struggle of useable rpm range, low end torque, high end horsepower, and upper RPM limit. I've lost some of the lower end punch you in the face torque, which has made the bike more rideable, which is great. I've gained a bit of upper end range and power. I'm still a bit constrained when trying to reach the rpm limiter (still have the cdi set to the lowest RPM set point, which I think is 12,500 rpms). Also, the midrange isn't quite tuned properly as noted by vibrations in that range. Instead of trying doing even more tuning to the current carb (pwk 28mm suggested), I've gotten a 33mm fcr carb. I should be able to hit the full 25hp and have full power range of the engine, and maybe get a little back in the low end by decreasing the restriction on the intake side of the motor. Don't have any good pics of the carb uploaded, but it's just a typical fcr carb anyway.

And, to prove that I'm making bad financial decisions in building this thing, I decided to upgrade the GPS lap timer. The one I had works fine, but you can only see anything from it once the session is over and you plug it into a computer. I get the feeling that at this point, me as the rider is one of the things holding this bike back from full performance. Real time feedback would help me get better, so I got a GPS lap timer with a dashboard.



I'm almost done making parts for someone else in my hobby sized machine shop, so next weekend, I'm going to start by making a fairing stay so I can mount this and a double bubble windscreen, and then start making a main fairing. I'm also going to use some modeling clay to reshape the tank to provide a little more leg support for leaning off. If I can get all the fairing work done, then I really want to spend the time sanding/painting for a good surface finish, and then make molds of all the fiberglass pieces. If I can do that, then it would be very easy to make new pieces out of carbon fiber.

Anyway, that's where I'm at with this project so far. Oh, and for anyone using the Racing Bros fork cartridges, I made new internal pieces so I could do the 1" fork extension, but aside from that, I noticed the thinner fork oil kept me almost maxed out on the dampening adjusters. I ended up switching to straight 20wt synthetic fork oil, and couldn't be happier.
 
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