Vision Tracker

[per_w_aberg]

Thanks guys! The handlebar, for Triumph, and the XR seat is from http://www.redmaxspeedshop.com/flattrack.html since the market for tracker style is dead in Sweden. Choosing bars is a gamble but I think were good. After checking the wiring and swapping coils I had it firing on all two with the choke. Some carb work and proper valve clearance is called for. Next up is strip down and paint.

[QBS]

Running only on the enrichner circuit usually indicates plugged pilot jets.

[Rikugun]

The bane of any bike not run for a period of time. Visions seem particularly vulnerable to the affliction.

[per_w_aberg]

Here's a video. http://youtu.be/Dzm4C3vi2Q8

[Rikugun]

If only it was that fast in real time! Cool engine stand you've got there.

When you're done will you do another short this time entitled "Tracker in Library"?  :)

[per_w_aberg]

When you're done will you do another short this time entitled "Tracker in Library"?

I'm not sure i follow. But I've done bikes in library like this one https://www.youtube.com/watch?v=ZLoumdZz9nw
On another occasion we had 5 MX bikes on display in another library promoting a newly started dirt bike club.

[Rikugun]

The bicycle vid was what I was referring to. Yes, another "short" film in the library this time with the Vision Tracker.  ;)

[sunburnedaz]

I know the brake posts were about 10 posts back but I wanted to chip in on this. I just did what you did and put an 11mm axial master cylinder from a CRF450 because in my riding of the dozens of bikes that I end up test riding after I finish fixing them the vision has the worst brakes in terms of hydraulic advantage and feel or what I call the ability to modulate the stopping force. Not that it would not stop. I could lock the front brakes up with less than a 3/4"-1" of pull but I had to put a lot of strength into it to move it that 3/4-1"

First the Vision does have SS lines and the MC and the caliper have been rebuilt and bled. Now I had a very very firm handle. So much so that if I wanted to do a quick but not panic stop it took a lot of hand strength and it was tough to have a lot of fine control over the deceleration rate and the lever moved very little.

So the 11mm MC allowed me to trade some having to use some more stoke length for some fine control and the ability to just about lock the front wheel up with 2 fingers. Now the trade off is that I do have to pull it farther but I like that because that's whats giving the feel I like. Pull it in a little for a gentle stop or pull in a lot for a quicker stop or pull it in all the way for a panic stop. Its almost too far the other way from being wooden I think a 12mm MC would be perfect but the only bikes I have heard mention that use a 12mm are from moto guzzi and ducati so they want some good $$ for those parts and the rebuild kits are a pain in the dick to source. So instead I am now looking for an MC that has a total advantage of less than the CRFs but more than the Visions. The vision MC had a total advantage of about 27. Lever advantage times the hydraulic advantage. The CRF450 MC has a total advantage when installed of about 36.

If you want to figure out how an MC will feel here is how you can calculate that out. (distance from pivot point to first finger / distance from pivot point to plunger engagement) x (total area of slave cylinder(s) / Area of MC bore)

[per_w_aberg]

I love this and use to say that the meaning of life is talking about stuff. And just do things, that we can talk about. I actually got 10mm MC in my calculations. I'm not overly worried about the breaks  thinking it will be better than millions of bikes predating mine. 

[Rikugun]

I love this and use to say that the meaning of life is talking about stuff

Good point - maybe I was too quick in dismissing the smaller mc... :-[ BTW, why didn't you use the 10 mm master - both it and the 11 are in the 14-12:1 ratio range preferred in the Vintage Brake article.

the vision has the worst brakes in terms of hydraulic advantage and feel or what I call the ability to modulate the stopping force. Not that it would not stop. I could lock the front brakes up with less than a 3/4"-1" of pull but I had to put a lot of strength into it to move it that 3/4-1"

I agree with sunburned the V does not have the best feeling brake lever in the industry - or at least the single disc setup I have experience with. But does it have less hydraulic advantage or just require more effort at the lever? Doesn't a larger mc piston provide more advantage with a given caliper piston? Is the "wooden" lever the result of feeling higher psi but at the expense of feedback/feel?

Yes a larger mc moves more fluid but acted upon by the force of the hand lever creates more psi (force x area) as well. Higher psi times any given caliper piston area equals greater clamping force. Unfortunately, the same pressure realized at the caliper piston is also felt at the hand lever. I guess a longer lever would then be needed to bring the relative "feel" back to where it was comfortable/controllable etc. Since a longer lever isn't practical but smaller bore mc's are plentiful, the latter makes more sense.

I went back and looked at the article previously linked. http://www.vintagebrake.com/mastercylinder.htm and it seems to apply to single pot and opposing twin pot calipers. He advocates a range of 12-14:1 for the single and 27:1 for an opposing two piston setup.  I'm not sure how other configurations figure into his chart but the Vision's (single pot) single and dual caliper ratios are outside the preferred rage at 9 and 11.5 respectively.

[fiat-doctor]

nope, smaller piston gives more advantage....   think of it as a smaller countershaft sprocket...
If we had them :)

[Rikugun]

Not the analogy I would have used but I've certainly been looking at this all wrong.  :)

In addition to piston ratios, I'd guess lever configuration may have a lot to do with "feel". Aside from varying fulcrum placement and lever shapes, leverage changes (more so w/axial?) throughout lever travel. As the lever moves the vectors to resolve change between at the piston contact point.  As the lever moves in, the push becomes more direct and more of the effort is going in the right direction. Not terribly scientific sounding but regardless, outcome isn't so easily predicted with simple first-order lever calculations. At least not with my education....

One thing I did notice was a bio mechanical thing. With a stainless line and overly large mc piston, the lever had very little travel before becoming "wooden". With fingers at nearly full extension there was little "finger leverage" exacerbating the high lever effort requirement. Simply loosening the lever adjuster screw to create more free-play moved the lever in where my fingers were in a more advantageous  position once the pads meet the rotor. This seemed to improve effectiveness but may not do much to combat unwanted wheel lock-up as described in the article.

[per_w_aberg]

I understand it like that the ratio determines if you get hard (no flex) feel and weak breaks, requiring strong grip, on one end and on the  other end you get flexy feel but powerful breaks. Your choice. A setup that requires a hard grip would possibly make dosing harder with lockup as a risk, not what you might expect.
My stock piston area ratio ratio was 12.83 with 15mm mc and 2X38mm pots. One pot gets me down to about 10mm mc for the same ratio, witch is a starting point. Then it comes down to applied force and some metallurgic/chemical/thermodynamic/alchemical limits to how much stopping power i can actually get. I like to clarify a common misconception about steel braided break lines and there superiority. Its not the flexible braiding that makes them good (non flex) its the Teflon inner tube. If you put steel braiding on a rubber tube you would only gain looks.

How about some pics?

Changing valve chims without the special tool is not hard and leave the chain in place. If you're a total dumb ass, like me you release both cams at the same time even though one has the valves springs compressed, that's plain stupid.

Let me throw in a nice looking bike i spotted at Sweden's largest bike show, Custom Bike Show in Norrtälje. I just sat there anonymously. Turned out to be a high concept build by the guys that did my sub frame and is of a BMW's new NineT that made a stir in the Cafe community. They got the bike from BMW with the order to make something cool, as did well established builders around the world. Maybe they over did it but that's alright. I feel close to it because BMW's Swedish designer Ola Stengärd was a big part of the original design. Read all about it http://www.uccycles.com/2014/04/18/chop-that-ninet-21408858

I'm suppressing a will to write about whats about to happen to my bike in favor of showing actual progress.

[Rikugun]

My stock piston area ratio ratio was 12.83 with 15mm mc and 2X38mm pots

That's not too bad. I think the USA 2 caliper Vision is 11.5.

Its not the flexible braiding that makes them good (non flex) its the Teflon inner tube

Yup

If you're a total dumb ass, like me you release both cams at the same time even though one has the valves springs compressed, that's plain stupid.

Not necessarily stupid. With 4 cylinder shim under the bucket systems it's unavoidable. Since you are the valve cover did you check cylinder head bolt torque?

That's a good looking BMW. If it were built here I would have guessed Roland Sands.

[per_w_aberg]

That's a thorough chart. I'ts getting serious!

Not necessarily stupid. With 4 cylinder shim under the bucket systems it's unavoidable. Since you are the valve cover did you check cylinder head bolt torque?

I did not, is that recommended?

The valve clearance needed typically 0.05mm more play and is now sorted. I think the bad idle was due to the fact that I omitted one of the braces across the carbs and that messed up my carb sync.

I'm on to bodywork and paint of the tank/saddle and that is a time consuming process. I finally found a color I liked, on a Skoda! One phone call to the car dealer gave me the color code and 1 hour later the spray can shop had it in a can! Living in the most populated are of Sweden has it's advantages. You wouldn't believe the recipe for that paint, 6-7 different colors are in there, black, red, purple, silver.. ..

I felt increasingly bad mounting the ruff bolts and nuts so I had the zinc treated. Going half way I had a box done in black zinc and left the good bolts as the are. That's not really seriously executed but good enough for version 0.1 of the bike.

I got a good looking fork brace delivered from New Zeeland thanks to POD, literally the other side of the world. Cool deal!

Enjoy the art installation in my back yard, called "Sleeping Power".

Your bonus sports picture is another art installation with practical use as seen in https://www.youtube.com/watch?v=9EjA0-3egX8

Per
Sweden, World Cup Soccer bronze medalist 1994

Give it up for Costa Rica in the soccer world cup, the country without an army and with the highest literacy in Latin America, officially going carbon neutral and with a population of only 4 million.

[Rikugun]

Your bonus sports picture is another art installation with practical use as seen in https://www.youtube.com/watch?v=9EjA0-3egX8

That field could double as a teaching aid to visualize the fabric of space-time's distortion by objects...  :)

I think the bad idle was due to the fact that I omitted one of the braces across the carbs and that messed up my carb sync.

Could be. I think that's why the second brace was added on later carbs.

Enjoy the art installation in my back yard, called "Sleeping Power".

Mount some tempered glass as a top and have yourself a chic coffee table.


The parts are looking good and will really add to the finished project. Attention to little things like fasteners really makes a difference.

[per_w_aberg]

That field could double as a teaching aid to visualize the fabric of space-time's distortion by objects...

Yeah, and that goal wood work would be a string.
Today's my big day! Started mounting and its a blast. In the end I got a tendency to faint slightly. That's when I realized i forgot to eat, ha ha. It's so sweet. Living in a crowded place i found a free zone where I could do stealth spray painting. It ought to be forbidden on account of pollution but there it goes. Black zink bolts are killer. The frame is semi gloss since i couldn't decide on gloss or matte. I did 5 passes with filler and 3 passes of spray filler on the tank before settling. Top finish is up next. Damn, it feels like I'm going for a Ride tomorrow :)

[fret not]

This is one aspect of the "human condition", that as you move closer to the horizon the horizon recedes.  Big projects like this one are in many ways much the same, however, at some point you WILL bring it to completion.

We are anxiously awaiting the visual results of your major effort.

[per_w_aberg]

When you're building a bike it's important to fika, that's swedish for coffee break, and a bulle isn't in the way.
Had a set backs with the paint. I used 1500 wet sanding on the metallic paint before clear got and ruined it. A new can of paint saved the day but the satin finish clear coat won't go on without looking patchy. For now I call it "Industrial look" and am focusing on the mechanical.
We have got some wiring going on and our "auto wall mart", Biltema, has got some nice connectors and wire protection. I don't mind some crude details on the bike like the wire strap thing on the head light wires for that function over form look. There's also a pic of the main switch conveniently reachable under the tank. How about my functional oil lamp? Ok ok, that needs some work :) I'll round of with something that actually looks like a bike.
Again it runs like crap! I'm leaning towards fuel pressure since I omitted the fuel pump which is not necessarily a good thing so I understand. Now there's work to be done sorting out the fuel system. I wouldn't be surprised if i have to change the jets a dozen of times, just have to figure out where to get the jets. For the silencer I made it really restricted as i did my old BMW with big rally car mufflers and CV carbs, bad combination. That one didn't run alright until I almost blocked the silencers with restrictors. I ended up running and sounder real sweet. Now there's  a couple of added parameters so we'll see. Seems like the promising ride is a bit of a way ahead.

Finally a pic of the sweet fork brace kindly given to me by forum member Prophet of Doom and sent the longest possible way on this planet, New Zeeland-Sweden. I assure you it makes the whole difference tightening up the front end, solid as a rock. Thanks again POD!

[fret not]

It is looking pretty good so far.  Are you going to use the original radiator, or something more compact?