tigcraft update

Prepare to drool...

All forked up

The box arrived from Traxxion Dynamics with my supermono forks inside.  Knowledge and experience are wonderful things, but sometimes come at a cost.  Considering what was done in terms of intellectual property and expertise, the cost was fair.  What I discovered was reassuring, as the problem I had with the forks was legitimate, and the solution I paid for was the only one possible -- so I had correctly diagnosed the problem.
As I said in an earlier blog post, I suspected the fork springs as being too soft for me and the bike.  There was some chatter out of corners, and the o-ring on the fork tube indicated that the forks were bottoming quite regularly, not under braking but under compression while cornering... not good.  While an increase in oil level helped, it was a stop-gap.  A book I recently bought about suspension tuning advocated treating spring rates independent from the damping process -- no amount of preload, compression/damping, or oil weight or level was going to adequately compensate for the wrong springs.  I send the forks to traxxion to get an idea of the fork spring rate, and then if necessary install and set up the correct springs for my weight.
The information I got back was enlightening.  The spring rates were a combo -- .55 in one fork, and .82 in another, for a combined weight of only .68.  Most bikes come with between .80 and .90 springs installed, with over 1.00kg springs available in some cases.  So stock, they were miles off.  Traxxion changed the springs out to .80 in both, revavled the forks, and serviced the assembly as well.  They were shipped back to me and they're ready to go back on the bike.
Bike Club reassembly will continue in the new year.  The student and I re-checked the vavles and they are within spec, according to the manual.  Really easy to do, actually, although if a valve is out, then changing the shim is a bit more complicated.
I'm getting some more responses from my sponsorship proposals, so I might get some additional product discounts and suppies for the season.  I'll post more news soon.

Oh yeah, Dave Pearce has been regularly threatening my marriage with tempting photos of some of his cool projects, both current things and past gems...
This is a MUZ factory supermono that my frame was based on...as you can see, the spec sheet and running gear is a tad higher than my supermono...

That's a self-supporting carbon-fibre tail section, and dymag wheels...

Yamaha 660 engine, bored out to god knows what and making copious horsepower.

This might be the leap at Cadwell Park.  Shipped to your door (in North America) for only 6500 pounds.  Go to http://www.tigcraft.com/ for more information.

This is pretty cool as well -- Dave is developing a custom chassis around the Ninja 650 engine.  Has an R6 rear swingarm, linkage, and shock.  Appears to be stock airbox.  Again, a CF tail section and light fuel cell and you'd have a bike to embarrass some 600cc racers!

And the other side -- some airbox tomfoolery possible -- check out the steering stem -- cut away, to perhaps allow a more direct ram air intake into the airbox???

new shoes

It was time to get some proper race kit -- the boots I were using were nice, light street boots, but after reffing for 2 years I saw first hand how important proper gear is -- with the flag, you get to see all the crashes and the results, not just the ones that happen to you or the guy in the pit next to you.  Roadracingworld.com does a great job of notifying privateers about sponsorship opportunities -- at my level the best I can hope for is a discount on parts -- I have never, nor will I likely ever get anything for free -- too old and slow for that.  But a discount is a discount, and when I sent my resume off to pilotusa.com, it was with the hope that I could get a deal on boots.  They came through.  They distribute prexport boots to North America -- not a popular brand over here, but big in Europe, and these, the spada model, were the top of the line and highly rated.  I got a killer deal on a new set, in the size and color I wanted.  While I was at it I plumped for a chest protector as well, as more and more racers are racing with these in place under the leathers.  Pretty pleased with the result:

Like all race gear, I hope I never have to use them.  Better gloves are next.  We'll see what I can find on eBay...

a few tweaks

With the bike apart again (bike club 2010), it was time to make a few subtle modifications to the frame.  Very simple, but knocked a pound or two off the overall weight.  As the engine mounts didn't use them, and no kickstand will ever be used, the lower part of the frame rails were removed with my tubing cutter.  Should also allow the fabrication of a slightly better gear change mechanism -- but that won't take place for awhile, until the engine is back in the frame.

You can also see how nicely a tubing cutter works -- a clean cut, with just a dressup with a file to get rid of any sharp edges.  Now just need to find some rubber plugs to stick in the bottom.

You will also notice a different remote resevior -- from a fox shock fitted to a vfr 750.  Checked the spring rates, and it should be in the ballpark for my bike's needs as well.  Triple adjustable and rebuildable as well, whereas the stock 900rr model was a throwaway item... and based on the leaking seal, it was time to throw it away!
In other news, just waiting for the 28mm needle bearings to come in the mail.  Atom-Jet will then bore the swingarm pivots to suit.  As well, with the engine out and at school, its time to check the valves.  Doubtful that they are out of spec, but while the engine wasn't run for long, it was run pretty hard.  Will be interesting to see what comes up.

swingarm project

I've never been 100% satisfied with the pegaso rear swingarm.  After hours of research, I found that based on photos seen online, that a suzuki rg125 swingarm might work.  Of course, those bikes were never imported to North America, so if I did find one for sale, it would be a bit of a leap of faith to order one and ship it here, in the hopes that it might work.  Like most used parts in the UK, this came cheap -- 9 pounds.  The shipping was a bit steep however. 

As you can see, it is designed to pivot on the rear of the engine case.  As well, it is set up for LHS drive chain, while the pegaso had to be "flipped" -- it also has a cool, GP-like banana arm style to the right -- intended for the expansion chamber to exit with some more room.  Dimensionally, it is quite similar to the pegaso swingarm.  However, in some key details it is different.  It has also been nicely powdercoated, but that is wearing through in some areas, and modification will require it to be stripped anyway.  And, while it has the look of an aluminum piece, it is actually steel.  Oh well, that means I can do any of the cutting and welding needed on the arm itself.

The key work that needs to be done first involves skills and tools I don't have.  First, the swingarm pivot axle needs to be bored out by 1 mm.  In order to use the proper parts, I need to be able to press in a 28x22mm needle bearing.  Currently it will accept a 27mm bearing.  So the front part needs to be enlarged by 1mm overall.  Secondly, in order to use the correct rear axle from the rs125 wheel, the wheel slot and the carrier needs to be bored out to 20mm.  My hope is that this work can be properly done in the first place -- so its off to Atom-Jet tommorow just to see if it is possible.  I really think it is, but it would require some creative jigging on the mill table for it to work.
Depending on how simply I can get this done, there is a slight possibility I can do this mod over this winter.  Luckily, the pegaso swingarm is still "fine", and will be kept as the fallback solution in case I hit a roadblock with this project.

tanks again

Supermono forks are on their way to traxxion dynamics for service.  Got the KR1S tank in the mail last week, and spent some time today doing peliminary fitting.  I think it is going to work OK -- need to take care of a few niggly things, like:

Need to determine the angle of the rear subframe - it does need to be jacked up somewhat, but I can't determine that angle until I have the wheels on -- need to set the seat height properly.

Petcock may not work in this location -- so I might have to move it somewhere else (slightly) -- it did come with the tank, so I'm currently soaking it in the same seafoam solution I used to clean up some carburetors.  Will be a long wait until Christmas before any major work is done on this bike -- forks and front wheel is waiting there for me.

In other news, it looks like the local club has decided to add an ultralightweight superbike class -- so the 'mono has a class to race in.  Will be a bit of an uphill battle against some of the bikes, but at least I don't have to line up against 1100cc Ducs and Buells!
Was able to source some Dunlop slicks for the 'mono -- the rare 155 width rears that were put on gp bikes.  Used, on order to see how well they work.  Got to be 100 times better than the Michelin street tires I have on there now!  My worry is that the 160/165 michelins slicks will be too wide.  Further, the stock, leaking, OEM rear 900ss shock is being replaced with a fox shock off of eBay.  A longer term project will be fitting a RG125 rear swingarm, in aluminum, to the mono -- hopefully I can get that to work sometime soon (perhaps not this year!)  That is coming from the UK, so it will get to me directly.  The stuff for the mz is waiting for me at Pop's place.

Plug!

Just wanted to make a willing post plug to the folks at Traxxion Dynamics.  They rebuilt my EX650 rear shock, and did, by all accounts, an awesome job.  While it will be months before I can test it out, one of their techs actually raced an EX before, and I think did some work with a Moto-ST team that raced in the states.  They sent back the shock with a shock dyno chart (I have no idea what it means), and of course it is spotless.  Spring rate was correct for my weight, and some revalving magic was done, as well as a recommended ride height setting.

Their website is:  http://www.traxxion.com/

Give 'em a call.  Friendly folks for sure.  I plan to send my supermono forks to them as well.  I need stiffer springs to suit my weight, and Mike and the gang think they can help.  Worth it from my perspective.  Sort the handling first, then spend money on the engine.

Forks

I was able to research and find out the proper bearings that would work to convert the R6 forks (including triples) into the MZ skorpion frame.  Ironically, the correct bearing set comes from a DRZ400!  The ID or bore of the bearing is 30mm top and bottom, and the OD of the cup is 52mm.  Not a common bearing, but a call to "All Balls" had me sorted out, and with the ordering information, I was able to get them from Transcanada within 2 days.  Took me about 15 minutes to check to see everything fit properly.

These are tapered roller bearings, and also come with dust seals.  I had already purchased a set of R6 forks and triples off of ebay for a good price.  Rather than go with more expensive USD forks, I went with traditional RSU forks, that still have preload, rebound, and compression adjustment.

While they look a bit rough, the upper triple is straight and intact -- perhaps a coat of paint will help things along.

Installed -- the frame will require a minor modification -- there is a little tap that is supposed to act as a steering stop -- however, it isn't long enough to work with the Yamaha forks, so it will have to have some material welded to it to work properly so there is some steering lock.

At the other end, the DRZ400SM rear swingarm has also arrived and been installed.  Need to find some axle sliders in order to set the rear wheel in place -- there are some on Ebay that also have provision for a slider/rear stand spool, which would solve two problems at once. 

Waiting on the KR1S tank to arrive to set the angle of the rear subframe.

swingarm is on

The Versys swingarm is on, just waiting for the rebuilt penske to come back from Traxxion Dynamics.  Need to add a little clip to secure the brake hose, and then it is done.  Chain to follow.

close shave

The FCR parts from Sinceros Speed Works have come in.  These are the jets, needles, and intake bell required to convert the 39mm carb originally off of a yzf426 to work with the DRZ -- essentially the same carb as sold on the E model DRZ, and also available as at kit for $500 or so.  I spent considerably less; here's hoping it works as it should.

You can see that this carb has provision for a throttle position sensor, which I am told is not supposed to be hooked up -- makes sense, as the carb was originally from a Yamaha.  Idle wheel can be seen to the lower left; red knob is for a hot start -- very important when MX'ers crash during a race and need to kick-start the bike in a hurry while warm.  Black knob is the choke.

Like all MX throttle cables, what came with the bike is far too long.  Will leave it as-is for now, and try to track down some brass ferrules in order to make a short cable of the proper length.  Ran out of them with my earlier Venhill kit I got from the UK.

Only one cable is needed, as the return spring action of the slide is considerable.  Not sure if I should bother covering the upper hole, as I don't intend to get a lot of dirt in there!

This is where the "close shave" comes in -- the lower bolt on the float chamber misses the frame tube by 1/2 a millimeter!  The whole conversion would have been a big "fail" had my welding or the carburetor forging been microscopically different.  Result!  According to all the experts, this mod alone should be good for a couple of hp.  Just need to get the jetting right for my application and altitude.  Won't bother trying to run it till the spring, as it is below freezing regularly these days.  Fettling on this bike is done for now.

Swarf and inspiration

Atom-Jet is making me the two spacers, and so I attacked the rear subframe, cutting off about 5-6 lbs in the process.  I shoulda done a before and after weigh-in. But here's where I'm at right now.  I had some 3/4" 4130 left over, so I replaced the passenger area and luggage rack with just the cross-member seen at left.

A lot of time was spent with the angle grinder, first cutting off large chunks of metal and then grinding off the remains.  There is more that could be done, but I wanted to stop here before I went any further.  Depending on how the tank fits, I might need to adjust the angle of the subframe, or add supports to prop the seat section up a bit.

I've also been looking online for some inspiration -- some sort of neo-retro look for the bike.  Over the course of the project, my ideas will likely morph and change, but here's a neat Hawk I found while researching fuel tanks.

I can see it has a 125 GP seat on a custom subframe, and the tank was molded from foam and wood -- not clear if it is covering an aluminum tank underneath... not keen on using a fibreglass tank on a streetbike.

Speaking of tanks, I think I found something that should work with my frame.  As usual, its from a bike never imported official to North America... so I found it in Germany, sold to me by a Dutchman living there.

From a bike called a KR1S -- a 250cc 2-stroke that battled with RGV250s and RZ350s in Europe back in the 80s.  A bit rough looking, but comes with a cap and petcock, and rubber bumpers for mounting.  Hopefully it gets here in one piece and is suitable.  The original tank is too small, ugly as sin, and wouldn't work with my oil in the frame idea...

another new project

I'm addicted, I guess.  Better than crack and only slightly less expensive.  Embarking on another 'mono project -- this time, for the street.  Plan on using the DRZ/KLX engine again, as I have a bare engine for mockup purposes, and a few spares and extra hardware that I can use... as well as experience with the engine. 

As for the frame, I am starting with a Muz Skorpion frame that I got off of ebay.  The Muz was normally powered by a Yamaha 660 single, so the smaller DRZ will fit in with no problem.  I also got a subframe for the engine, but its about 10 lbs heavier than need be -- for a passenger, as well as to accomodate luggage and two exhaust pipes.  No thanks.  The angle grinder and cutting wheel will get some use.

I also found a DRZ rear swingarm for $14 -- this is the S version, so I want to find an SM for the final version -- a bit shorter, with proper streetbike axle blocks.

As for how the back end will be suspended, I'm thinking of going retro with twin rear shocks, or perhaps a single offset rear shock a la Norton rotary racer or ducati sport classic.

Allegedly a R6 front end bolts on fairly easily... I have acquired a set of 99-02 front forks (the RSU version), and a front wheel with twin discs for only $19 (the forks and triples were just over $100).

As for what the final "look" of the bike will be, I'm not 100% sure on that -- while a complete idea should be in place prior to the welding bottles being opened up, there are some mechanical things I need to develop or create, that I want to put into practice on this bike.

The first involves the oil tank.  I need a minimum of 2 L of oil for the dry sump engine.  What I would like to do is "hide" it, by incorporating it into the frame.  The DRZ400 dirtbike did this with a rectangular downtube on the stock chassis.

You can see engine mounting tabs just aft of the steering head.  The idea would be to use a 2.5" OD tube (with some jiggry-pokery to get the right volume) to mount to the front engine mount on the frame.  One would bolt to the other, and then the proper fittings would allow the hollow front engine mount tube to act as a oil tank as well.  The rad would mount to that, and etc, etc.  Of course, before I do any of that, I need to mount the forks in place, and create a "rolling chassis" -- need to get the angle of the dangle of the rear swingarm, and finally determine how long the front engine mount will be.  You can see some old 2.5" tubing in place for mock-up purposes already.

When dad delivered the frame and parts this past weekend, we also drilled out the frame engine/swingarm mount hole to 17mm -- even had a nice bolt at the right length hand I can use.  As you can see in the pic, a few spacers need to be made to center the swingarm (and ergo, the engine) in the frame.  I've got some nice aluminum alloy material to start with.

This can hopefully be an ongoing project to play with over the next few years... I'll keep everyone posted with updates as they come in.

Swingarm Swap

Started the process yesterday to switch out the steel ex swingarm for that of the versys.  Old rear swinger cam out fairly simply... and it looks like more of the parts are interchangable than originally planned, which will save me some money in the swap.  Did some comparison of part numbers on Bikebandit.com, and I already have $60+ of reusable parts, in the form of spacers, oil seals, etc.  I still need to order some items, but it will be far cheaper than I thought.

 While I was at it, I also removed the front countershaft sprocket.  I have a leftover racing chain with low miles that is slightly shorter than stock.  My hope is to shorten the gearing for racing, but go to a 13-43, rather than the stock 15-46.  The original chain had to be cut off anyway, so I went with a 520 set.  For longer tracks, I will switch to a 14-43, essentially back to stock gearing, but with the smaller sprockets overall.  Dad's bringing those in for me in a week or 2.

The bike is held up by a stand that I originally built to pass through a hollow rear axle -- this time, I just put a 3/4 inch tube through one of the hollow frame spars, and it lifts the back end up without using a rear stand.

The shock will also be sent out for a rebuild and revalve -- not sure whose weight it was set up for, and it is also weeping a bit around the seal. 

Note how much more beefy the rear swingarm is from stock -- and its still 4 lbs lighter!  Rear brake caliper hanger and caliper, along with the rear wheel spacers can be reused.

Weekend Education

Picture it -- glorious +26 degree weather in late September.  The weekend -- no work.  A new bike to break in.  Races being taped on the PVR... get out and enjoy the sunshine.  Which I certainly did, until I was about 1 mile from home after a lovely 50 mile ride (restricted to 39mph according the max revs break in according to the manual).  Me and the KLX are getting along famously.  Light, easy, fun to ride even with 20 hp, and more fun to be had when I can open it up after break in.  The supermoto tires mean that I can go through the 2 roundabouts in town without even braking, sticking my leg out with style.
On the way home Sunday, I approached the 2nd roundabout when a young kid in a Caddy pulled out in front of me -- he misjudged my speed (I wasn't/didn't need to slow down)... while he left me a bit of room I could work with, he then decided to stop dead... why, I don't know.  My brake hand reacted faster than my left foot, and down I went in a lowside with a locked front brake.  Like my roadracing crashes, things slowed down.  I saw the rear bumper approaching my head as I slid along the ground; I enjoyed the painless sensation of my Sidi boots doing their job, protecting my left foot trapped under the bike; I immediately felt pain in my hip, but the numb type I generally associated with a hard bodycheck; worst of all, I could feel my light jacket rolling up my arm towards the elbow, leaving my forearm to make corrosive contact with the pavement.  Then, silence.
I was conscious, did not hit my head, and I avoided the car.  The klx was still put-putting while lying on top of me... although I was able to reach down and hit the kill switch with my right hand.  The driver came out from his car, and a fella working on his yard also showed up.  Yard guy picked up my bike, while caddy boy claimed it wasn't his fault (was it...?).  He suggested we exchange information, but to what end?  My bike was remarkably undamaged save for a few minor scrapes.  My arm and knee were a bit of a mess, so with no information to exchange (single vehicle accident) he left.  Yard guy stayed with me to make sure I was OK, looked at my forearm to ensure that there was no bones sticking out.  I shook his hand, started up the bike, and went home for a date with the hydrogen peroxide and an old toothbrush.  Thankfully Kate was not home yet and I could howl in privacy.

The worst of it, 2 days later...


I've been riding since 1997, and this is my first street crash.  Ironically, I wasn't speeding, I was on the LEAST powerful bike I have ever ridden on the street, and I was a mile from home.  It was a day I decided against my leather jacket... my choice.  I did have a helmet on, I did avoid the other car, and I did avoid serious damage to the bike... my race-trained habit of "looking through the turn" avoided a more serious rear-end collision.  My boots saved my feet -- had I been wearing sneakers, yikes!
2 days after, I am able to put things into perspective.  This was a real wake-up call for me.  This little bike was supposed to keep me out of trouble, and while it crashes about 1000 percent better than a sportbike, it can still be somewhat dangerous.  What have I been reminded of:
1.  Never, ever, ever trust other drivers!
2.  Always wear proper protection -- where I was hurt the worst, I was the least protected.  My bottom half was covered in jeans -- still some damage but minor.  Had I had a leather jacket on, no injuries to the arm!
3.  When in doubt, chicken out (on the street, at least) -- I had been through that roundabout many times before, much faster, but there was NO traffic -- much more margin of error.
4.  My wife is a patient woman.  She made the trip to the pharmacy for more supplies on Monday.

So no repairs to the KLX -- scratches have added character to both me and the bike.  No missed work, although I am stiff and sore all over.  Again, could have been much worse!
And I got back on the horse on Monday -- rode for an hour in the warm weather again -- with a leather jacket! 
Dad, if you're reading this, don't tell mom!  If she does see it, remind her that once again, RACING is safer than riding on the street!  Keep the rubber side down, everyone!

Carb Diet

The YZ427 carb showed up.  In decent condition, but I soaked it in a product called "Seafoam" to help clean it up.  That, and some work with an old toothbrush did a good job.  Next step is to get the right jets for it -- Sinceros Speed Works to the rescue.

The wierd thing is, it looks as if this carb will fit under the tank?!  I did need to adjust the underside with a brass hammer somewhat, but it now fits fine.  Hmmm.  I also intend to pressure test the tank again to make sure my welds are holding up.

Great Weekend

Really enjoyed the last weekend of the season -- got the reffing done on Saturday with only one bad crash (rider is OK), and the hit the track on Sunday.  Was happy with how the comfort level came back -- made some good passess, picked up speed pretty quickly, and also didn't surrender spots other than to bigger bikes on the straights.  Even caught and out-dragged an SV650 -- of course, not in a race situation, but it seems that the bike has some decent speed compared to its competition, even with stock gearing.  Was a very windy day, and the fairingless bike ran well.  In fact, the mono, with its full fairing, was being tossed around quite a bit -- more likely due to its weight than anything else.  Got to the point on the mono where I wasn't even braking for turn 1 -- just pop out of the bubble, downshift once, and hold on.  Handled pretty good!  Again, some chatter and sliding through turn five on the little bike.  Not sure if that's due to the tires (the street-based 2CT michelins) or to the suspension.  Need more time to sort it out.  Did 4 sessions on the ex and 2 on the mono.

Had the bikes loaded on the trailer a few days prior -- school had started up and I was spending some long hours -- did not want to wait until Thursday night to load up, in case I was delayed...

Trailer held up OK, but I'm keeping a close eye on it -- its covered lots of miles over the past 11 years, and has hauled more than just bikes.  Might be time to get something slightly bigger -- no extra room on the deck for anything!

No shots of me "in action" that I've seen, so I can show you tire wear -- fascinating!!!  The michelin slicks were awesome!  Not sure how old the tires were, and while they were sliding a bit out of turn 9 (asphalt, not concrete), everything was controllable.  Nice wear pattern, no cold tearing despite the lack of tire warmers and the cold ambient temps.

Of course, for me to be battling at the front, I need to find 4 seconds somewhere...!  Next year!

I wondered about the bellypan in right turns -- while it did touch down, it acted as a gauge (along with my knee) as to what the suspension was doing at the back.  I need to get faster through turn 4 -- there is a bump right as you turn in that upsets the bike -- the bump carries across the entire width of the track, except for a 1' spot roughly 3' out from the inside.  On a clean lap, you go for that spot -- otherwise, you grin and bear it.  Pegs and levers were fine -- no contact.

So now its time to get the bikes ready for winter storage -- I've removed the Cool-Aid from the ex and replaced it with glycol -- gonna do the same with the mono, although its running straight water.  Winter plans include a rear swingarm swap on the ex, and a shock rebuild/revalve -- the machine is running perfectly otherwise.  I've built a stand that will hold up the rear of the bike while leaving the swingarm free to be removed.  With the mono, my 1 gal alloy tank has arrived, as well as the carburetor.  Gonna test fit the FCR, then clean it up and jet it for the DRZ.  Mounting the tank will take some work, but I've got a few ideas.  Off to get some pink foam insulation today.  As usual, stay tuned.

no excuses

For all intents and purposes, the ex is ready to roll... no comprimises with tires, exhaust, suspension, etc... all that is left is the fine tuning and me getting up to speed and to grips with it. 

The Muzzy exhaust came in earlier this week, and was quite easy to install -- just headers and the muffler -- 5 bolts in total.  Fired it up -- sounds pretty rorty... might be pushing the db levels at some tracks.  When I went to mount the bellypan the headers and collector pipe (as short as it is) fouled on the pan.  Spent another couple of hours cutting out a section of the bottom of the bellypan, and riviting in an aluminum relief panel.  The end result is still oil tight and should work OK.  The muffler fits well within the rear cutout and looks pretty stealthy.

  

Mom and Dad stopped in for a visit on their way west -- Dad played "mule" duty and hauled in some proper slicks (Michelin 250s from Motorace) as well as a few Versys parts for the swingarm conversion -- swingarm pivot axle and rear axle and adjusters, so that should help with finding the other hardware for installing the new rear end.  The Michelins can be a PITA to install, especially if they've been stacked on their sides (like they all have), but with some massaging I was able to get the beads to seat.

As I said, mechanically, there should be no issues with the bike -- everything works, nothing is compromised, all that's left is optimizing things like the rear shock (it may not be set up for my weight), and getting used to the bike.  I really hope the "experiment" that is the decision to go fairingless works out OK.  The streetfighter look is not something I am really keen on as streetbikes, but I still wonder if a full fairing is necessary on a 65 hp bike -- it is the balance between aerodynamic streamlining and coefficient of drag.  Short of a wind tunnel, I've go no way to prove my ideas.  The truth will be in my right wrist, next weekend.  The final round of the year is on the 11/12 weekend, and after my refereeing duties wrap up on Saturday, I plan to get in as many laps as I can on both bikes on alternating sessions on Sunday.  Hopefully my improved fitness will allow me to ride all day.

On the 'mono front, one of my long-term goals has always been to fit a FCR carb to the engine.  Google drz/klx400 and 39 FCR and you'll have hours of reading on the benefits of fitting this to the S/SM bikes (the E model got it stock).  I am still certain the 40mmCV I have right now is an improvement over the 36mm carb that came standard.

I was able to source this item on eBay for a good price -- I've also found a reputable page describing some jetting settings.  This is a popular carb, fitted to many models of MX bikes; therefore, aside from assuring its a 39mm, I will likely have to switch out some jets to get the carb to run properly.

Another fabricating problem is going to rear its head as well -- back in late 2008 when I was modifying the tank to work with this frame, the underside of the zzr250 tank was adapted to suit a CV carb.  In general, these carbs are "shorter" from top to bottom and so I modified the tank to suit.  A buddy of mine has a DRZ400 SM bike, and bought his own 39mm FCR.  There are no clearance issues fitting this carb to the stock bike, but I noticed at the time that it appeared a FCR would not fit under the modified ZZR tank I built... so with all mods, there is often a carry on effect.  This might mean a new tank!

ZZR250 tanks are a dime a dozen in the UK, but very rare in NA -- they were only sold in Canada... and, the only one I've seen in a year is stuck on eBay for a very high price -- fair enough, its new, but not what I need.  Again, in the quest to "lose weight", I did some research:

• 1 gallon of fuel = 8.33 lbs! 
• So if you put 2 gallons of gas into your bike for a 15-30 mile sprint race, you are carrying around at least an extra 8 pounds of ballast.
• Gimli sprints are even shorter, the tight track results in lower speeds, with less fuel demand
• A KLX400 single gets "great" gas mileage!

So, likely any new tank would only require 1 gallon of volume -- I would just need to remember to keep the tank full... and save more weight!

The plan now is to find a decent quality 1 gallon fuel cell -- go kart racers have these in aluminum or even plastic.  I'd prefer the alloy, but we'll see what I can find for a reasonable price.  Mount it in a suitable location, and then cover up the sharp angles by gluing pink foam insulation to the tank, and then cutting, sanding, and shaping the big block into something resembling a fuel tank.  The pink final copy is then covered with epoxy resin and fibreglass, sanded, and then painted like any regular tank.  About the same work as modifying a stock steel tank, but with the anticipated result of a lighter tank (albeit with less volume).

Finally, on a sad note, many of you know Peter Lenz was killed at the Indy MotoGP.  I have a very loose connection to the fellow -- I emailed and spoke with his dad awhile back when I bought some of his old bodywork -- the tail section on the 'mono was some of his old stuff.  I bought it used with some crash damage, and I had to admit I was a bit jealous of the kid when I was prepping the piece for painting -- the underside of the tail section had a really neat professionally-made decal with his name, number, and a pile of sponsors.  A real pain to remove!   Looked pretty cool and I was jealous of the then 12-year old.  His passing reminds me again how my life has been one big stroke of luck/Lucky Stroke in comparison.  The only consolation is that he died doing what he loved to do, by no mistake on his own.  Pretty cool legacy for a 13 year old.