New exhaust is built - now with photo's and a Sound bite

[fret not]

BRAVO!  Nicely done.

[treedragon]

Thanks to one and all for the responses, please understand this exhaust is not just my effort........... Without my close friend (with a passion for these engines) this exhaust, and cams, would not have happened, and there is more to come......... He saw the potential and ferreted out the history for these engines many years ago and that combined with my "well why should I leave well enough alone" attitude........  ;D  ;D


I got some more mileage in today and what impressed me first is how it doesn't matter which gear you are in around town, there is useable power everywhere, 5th is best, it has just the right note for the occasion and doesn't disgrace itself for power at low revs, (2,300rpm)  ;D  ;D   
I will see if I can come up with a sound bite.

Then it was into the hills and the tight and twisties, no more worries about when to overtake between corners, she don't need nearly as much space and I am going to find the uprated front brakes veeeeery useful.

It is a totally different bike now and requires me to revise how I ride it.

Interesting point: it runs around 10 degrees C cooler than before...............  not expected, however that may change with .... um improvements  8)  8)  8)


Pullshocks - It was made up out of pre bent 316 stainless tubing for the most part and off the shelf Y's that I suitably panel beat to submission.

Iain - be good to see the Weber manifold. The carb I am using is a fully reconditioned unit from a Paso and I am looking at reshaping the inlet tracts from that.

roro - yes volume upgrade for sure, these bikes were strangulated from release. I'm picking there would be good improvement with standard cams also, however I very strongly suspect a change of carby's will also be beneficial for best results and preferably a port job on the heads (that is a little down the way for me, but not toooooo far). Of course another thing will be the exhaust vacuum pump for the crankcase, (now that is much closer we were talking about it today, ie the XZ be the guinea pig for the company race bike)  8)

unitivegreybird - you're onto it, although I do not specifically claim to read to it...... well not that I would admit too (other than words muttered after the occasional blood offering to the god of mechanic) I do know it likes me.

Re-Vision - fair enough comment, but in the flesh it doesn't seem to stand out so much. I wanted to remove the Termignoni sticker as I am not into branding but I am not allowed.............. sigh.   The carbon is a bit over the top for me but then again it is light (I have saved many kg's on the exhaust system) and it does sound very nice, and I mean that, VERY nice.


Of course there is always the eternal question how should a YamaDuc 552 look  ;D   ;D  ;D  ;D  ;D

[YellowJacket!]

WOW!!!!!

:)

Awesome job!

David

[Raj1988]

HOLY SMOKES>>> If I fly down to NZ would you let me ride it???

[vadasz1]

That is one fantastic piece of work there treedragon.

I would like to know if you modified the rear y-pipe.  My ideal connection would to have the rear y-pipe fit like the front, meaning that we get rid of the rear clamp system and just use a regular flanged y-pipe.  That would solve many leaks that we have come across.

If you can post pics of the rear cylinder exhaust it would be appreciated.

[treedragon]

vadasz1 - The rear Y is the same as the front without the initial curve, just out of the head and straight down to where it curves under the bike. I have no idea why they had a curve in the factory unit.
The only original bits are header ends which I turned on a  lathe to take the new pipe size, so no bizarre clamp system just the original flanges and bolts.

[kwells]

So when's the 2nd one going to get produced?

[treedragon]

Over the weekend I got to do a ride with the Ducati boy's, (not many as it was raining and blowing and all that stuff that seems to keep so many home....)

The first thing I noticed confirmed the bike is running cooler.

Now this is a well used motor and I am accustomed to smelling an oily fumy smell from my catch bottle just under the front of the petrol tank, that smell has entirely gone and those behind couldn't smell it either, mentioning it to me without any prompting on my part.

My fuel economy has gone back up to "normal" compared with the loss when I had put the new cams in (when I lost so many k's per litre). I haven't done any sensible riding so I can't yet say it totally equals what I had before this whole cam/exhaust thing, but it is looking sort of hopeful as I am within one k per litre on the "going for it side of things"  ;D  ;D



Soooo it's the exhaust driven, crankcase vacuum pump and the Weber carbs next but that will be another post..........

.......as will my current experiments with a Marzocchi, fully adjustable, rear shock (some 35mm longer than standard) keeping in mind the XZ's rake and trail of 26.4 degrees and 118mm is considered less than optimal these days and maybe I should tread carefully  :o  ;D  ;D

[Rikugun]

Thanks for the continuing updates. Very interesting regarding mileage and the apparent reduction in blow-by gases. You may have stumbled upon the fountain of youth for Visions - big lumpy cams and even bigger free flowing exhausts!  Can't wait to hear what the crankcase pump does  :D

[iain]

I have seen it with my own eyes this work of art , after a weekend trip to nelson, not only does it look good it sounds bloody amazing..

Iain
NZ

[artbone]

It really looks great but would never work where I live. First tope (speed bump) would tear it off the bike. Is the purpose of the big loop from the rear cylinder to make the front and rear equal lengths? And are they an equal length? They don't look like they are but pictures can be deceiving.

It's really a beautiful piece of work and I would love to hear it.

[treedragon]

Yes they are fairly close to the same length. We worked with a number of standard bends (or sections of) mainly by eye going for what looked right and this is the result.
It actually has better clearance than standard when it comes cornering, (although I pinged them first run under duress...  :-[  :-[  oops). 

The sound really IS rather nice............ no way better than that actually  ;D
Now they have a few kilometers through them they have mellowed just a little with carbon build up and I so like the sound I tend to ummmm....... forget to put in my earplugs............. and this from someone who likes quiet bikes.

Since the picture was taken I have actually raised the bike a little with the Marzocchi rear shock as I noticed the other night when low beam seemed just a tad close to the front tire. I have been over / through some pretty mean bumps since, and at full compression and with no worries.

 

[treedragon]

Just a short soundbite.
I happened to have my camera on hand while I was starting the bike so I recorded a movie and extracted the sound.

This is what it sounds like at idle on partial choke. It's not as nice as the real thing particularly as it was tucked away in a corner full of echoes but at least it gives you an idea and it is a chance for me to test adding a sound bite and see what it does to my bandwidth. I will likely do a better one at some point.................

[fret not]

Sounds good, but not as extreme as I anticipated considering the cams and your adventurous penchant.   8)

[The Prophet of Doom]

Sound at idle is hardly a fair comparison of extremeness.  I'm guessing that since it's got no airbox things get pretty noisy at WOT. 

[iain]

it sounds 100 times better in real life

Iain
NZ

[fret not]

Wild cams tend to cause an uneven idle requiring  higher idle speed.  This one sounds fairly smooth, not loping or erratic like so many hopped up "competition" machines.

[treedragon]

Good point fret nut

So from this we can take that despite the much increased lift and duration, with it's corresponding extra top end noise at low revs it is still not that "wild",  so let us consider in the other direction then......

This could tend to support what I have said on a number of occasions, the detuned XZ motor that Yamaha finally released isn't a patch on what it could be................

This is undoubtably a much improved engine with the Cosworth cams and new exhaust, and will be even better when I get some decent carbs on it. The plug color say's it is running fairly well, but the sooty exhaust residue (over and above our lousy fuel) combined with it running 10c cooler than usual tends to indicate to my mind that it is going to run a whole lot better when it gets leaned up a bit and it might even get lumpy in the idle as well.

Meantime I notice my rear tire is not lasting like it used to and I'm feeling I need to uprate the rubber as the rear is a bit borderline in the corners now when being a bit heavy handed on the throttle and also I see it is obviously not going to last the expected distance.......  ;D  ;D I might try the Pirelli Sport Demons next time round as I can get some for a reasonable cost.

 

[Rikugun]

I'm feeling I need to uprate the rubber as the rear is a bit borderline in the corners now when being a bit heavy handed on the throttle

Or just slide it out of the turns like a GP rider!  ;D

[Charmac]

First off... Treedragon great job, i think we all knew that the V was a wolf in sheeps clothing, you have renewed my exitement in my rebuild.

I know i dont come to say very much, but i try to read as much as i can. My first vehicle, my first large purchase as a young man was the Vision, which i bought on the spur of the moment and was never sorry for the purchase. Althought at the time it had a different look than most other bikes of the time it was sometimes made fun of from those who knew little of it. And because of the size.. i was always asked if it was a 750.
The more i rode the V the more i grew to love this bike but after 2 years of ownership it was stolen. For reasons i have long forgot, i did not own tanother bike but always missed having the Big V. Years have gone by and kid grown up has freed up some cash, i found a the current V i now own with renewed exitement in the rebuild, all i need now is the time to work on her. I have been endlessy surfing the net and this forum for ways to make this V mine the ideas are flowing thanks to you all for providing your guidance and wisdom of the Big V will give the confidence to get it done.

Here is a link to an article that some or most have seen in one form or another but here it is anyway: http://www.sooperarticles.com/automotive-articles/motorcycles-articles/some-things-about-yamaha-xz-550-motorcycle-921820.html

Treedragon i look forward to your continued efforts

Thanks