Tuesday, January 25, 2011

planning and priorities

February is upon us soon, and before I know it, April will be here and the trip to MAM with the boys.  Next thing we'll know, the race season will be up and running.  As such I've decided to put the MZ project aside for now and will be concentrating on making sure both bikes are ready for the season.  The 'mono is still at school, with a number of things left to do to complete it -- again, lots of time remaining, but other things always get in the way of a plan not officially scheduled, and which always places second to the admin stuff I need to do first.  What is left is basically reassembly, but I would like to make a proper throttle cable of normal length... but that's it.  Those supplies should be here shortly and my student assistant should be able to lend a hand to get that job done.
In the interim, I've been coming up with 2011 and beyond plans for the mono -- the 650 will remain as is, and could eventually find its way back onto the street depending on how the supermono progresses.  The next step is to address the aerodynamics and rear swingarm... this won't even take place until next off season, but I've been keeping an eye out for some deals, and mocking up/sketching out my vision in the meantime.
More modern and lighter rs125 bodywork has been found for a good deal.  This is fibreglass, and should be half the weight of the OEM stuff I've been using currently.  The gaping "intake hole to nowhere" on my current fairing can't be helping my cause, and so this stuff should be an improvement.  I'll do some test fitting when I have the time this summer --  a new upper fairing stay may or may not be needed to work with this stuff.

A lot of my thinking about aerodynamics, specifically with the wee 400 came from this video -- an interesting study in drag...



The next project has to do with the rear swingarm.  I've spent some time with the RG125 swingarm, removing unnecessary tabs and brackets, and getting atom-jet to modify it to work with the engine and the rear wheel.  It's ready to go, all that is left is the fitting and alignment, and coming up with a side-mounted shock arrangement.  Not unlike the ex650/versys, the idea is to use the "bow" in the swingarm as a mount for a cantilever shock mount, and then attach that to the frame.  I'm thinking a 900ss shock would be a starting point.  You've seen a pic of the ex, here's one of a home-made aluminum-swingarmed supermono...

Spring rates would be a wild guess to start.  This would then result in a drastically different rear end to the bike, incorporating a different tank, different tank mount, different shock orientation, new subframe, a different seat, etc. etc.... that's all as long as the engine and bike in its current configuration is reasonable competitive in ULGP...
Carbon fibre wheels!  Sheesh!

Here's the early vision, from my twisted mind.  Photoshop lessons, anyone???

Old skool, analogue product development...

Sunday, January 16, 2011

molds


Need to make a mould to cover up the rearmost tank mount.  Used a portion of a peanut butter jar (plastic), some mold release compound, 2-part fibreglass resin and hardner, and some cloth.  Made a female mold first, and am now making a proper mold to attach to the seat unit.  Will keep the mold as it will also make a nice "scoop"... for "whatever".

Monday, January 3, 2011

put down the torch and ride

Over the past few years Wilson, Doug and I have been doing a bit of ice riding... I won't call it ice racing (yet) as we still go pretty slow, and I think only once did we have 3 serviceable bikes running at once.  The winter does a number on machines normally designed to run above freezing, with my ttr being the most reticent to start and idle when it is far below zero.  The good news is, keeping the 125 running at -15 degrees celcius is easy, you just pin it... and "pinning it" with 11 hp is not too dangerous!  My ttr again was the only machine that would run properly this day, with Wilson borrowing it in the fall and doing some magic with the carburetor -- his bike, Doug's thump pitbike would only seem to run on choke, and only until his rear tire went flat.  My tires have stayed airtight for a few years now, mainly due to running 3/8" koldkutters and lining the tire with a mountainbike tire between the maxxis and the tube.  A pain to put on, but it seems to be working.
Of course, to "dress for success" in the cold Canadian winter requires some specialized equipment -- layers are good, lined coveralls are nice, with a neckroll, big boots, leather mitts/gauntlets, and definately a full-face helmet.  Of course, said helmet needs the visor open at all times... see "frozen boogers" below...

As usual, Wilson did all the work as the track is actually a frozen slough near his place.  The owner, who rides a Harley and is good friends with Wilson lets us out and ignores us while we make noise.  On occasion he comes by and chats, shakes his head and says we're both crazy.  With noses running due to the cold, and then freezing to our upper lips and chin, and even forming booger-based icicles on our helmet chinbars, he's probably right.  In order to create the 5-turn masterpiece, Wilson went out with a snowblower and carved out a circuit on the frozen pond, cutting though several inches of snow with the consistency of concrete.  Well, Estoril was booked this weekend, so we would make do with this!  This is a pic of me taken by Wilson -- note the perfect form and massive speed.  Better than playing MotoGp on the Wii.
This is a short video I took of Wilson early in the day.  It will give you a sense of the incredible speed and massive talent he possesses.  A little known fact is that Wilson raced dirt track in 1981.  I was 10 years old at the time... as you can see, the passage of time has not dulled his sliding skills.  How this transfers to racing a TZ250 remains to be seen.


Next we have a shorter video of me taken by Wilson.  Hmmm, a bit sketchy -- I suppose I'm having a hard time coping with the horsepower of the bike.  By the end of the session, we were both turning competitive laptimes (around the 25 second mark) but were getting tired and falling down a bit.  The front tire was also starting to push quite a bit -- investigation showed the kold kutters on the left side of the tire were starting to pull out somewhat.  With no dunlop tire technician on site, we decided to call it a day.  Future plans are getting my 150 out on some proper tires for some more fun.  What did YOU do yesterday?
BTW, it's -25 degrees celcius today -- that's -13 fahrenheit.  Stay warm, I'm going out into the garage...



Saturday, January 1, 2011

gettin' jiggy wit it

My apologies to Wil Smith... spent some time coming up with some subframe options for the mz -- I was able to score a rear tail section from a TZ250, brand new, for $25... so with this back home I began to see how well it would mate to the KR1S/MZ subframe combination... not very well, unfortunately.  So I removed the MZ subframe and decided to build one from scratch.  I decided to use mild steel from Canadian Tire, as it is far cheaper than 4130 and if I screwed up or came up with another option, it wouldn't beak the bank.  I quickly threw one idea together, welded things up quick with the intent of doing it again properly if it worked out OK.  Looks OK, but things weren't properly square, and it turns out the seat height was too high for comfortable use by a short-arse like me...
You can also see the R6 forks and front wheel on in this shot... while the seat orientation looks OK, when you add in the height of a 160 rear tire, the seat height ends up being 34 inches -- taller than the ex650!  So, the basic idea is sound, a combination of square and round 3/4" mild steel tubing will be used, and using the rough draft as a starting point, I began construction again, using a lot more attention to detail to make sure everything was properly square this time...

This is a little jig that I have plotted out using a large square and some scrap wood.  The piece to the left has the attachment for the rear of the tank tacked into place.  The longer piece to the right supports the seat section.  Using a protractor, my tubing cutting jig, a bandsaw and a disc sander, I've got the first of two pieces (the diagonal one on top) set in place.  I need to make a stop at Canadian tire for some more material, as well as the welding supply shop to refill the bottles.  Dad said when he built his airplane, he essentially built it twice, as the first try for each part he made wasn't up to snuff.  I hope I don't have to build everything twice as well, but subframes can be tricky, and I needed to see it in a draft form first before proceeding with the "final copy"...
And courtesy of Dave Pearce (Mr. Tigcraft) here is another piece of bike candy -- that's a KTM 690 engine, and a composite aluminum-chromoly frame.  Don't drool on your keyboards, folks!

Happy new year, everyone!