Mikstr's VTR

[mik_str]

Update : my carb slide experiment didn`t work out (although it did prove useful, read on....). When I opened up the carbs, I noticed that the slides had a third lift hole (as per the DJ installation instructions). I replaced them with a set of slides (kindly donated in the name of science by a fellow Superhawk forum member) which had one stock size hole (OEM slide has 2, about 2.5 mm dia.) and one 5/64" (for a total area roughly half of the 3 hole slide). The result was much worse (seems I misread the situation…..). Throttle response was abysmal (felt like I was riding a Harley, lol). So, I put the 3-holers back in, backed off the fuel screws an extra 1/8 turn and shimmed the rear needle an extra 0.010" (rear cylinder runs hotter). BIG improvement. My theory is that it was a bit lean on the pilot/fuel screw circuit. It is now very close to perfect. However, based on the testing with the smaller lift area set-up, and because as I have a set of extra slides to play with, I will likely try increasing the lift area slightly (still feels as though the slide is not opening quite quickly enough, agaion, based on what I felt with the earlier experiment). I prepared the extra set I have with the two OEM holes and drilled two 5/64" holes (total four holes), this nets an increase of about 10% on lift area. It is just so damn close to perfect now, this may just do it……..

As for the TPS setting, a chap who used to be on the Superhawk forum claims to have dyno tuned a few dozen VTRs and says that he found (trial and error) that 430-440 ohms is the magical setting (slightly lower than the setting recommended in the shop manual, which is 500 ohms)…..

[sirch345]

Micky, I knew it wouldn't be long before you started trying something to rectify the slight balking on quick throttle openings

Going by your thoughts on the problem I would have expected what you tried first to be an improvement too. It certainly appears you are getting there, and I'm sure you will.

Thanks for the info on the TPS.

Chris.

[mik_str]

Woohoo!!!! JUst picked up an awesome second-hand Moriwaki carbon lower for the old girl

http://www.superhawkforum.com/forums/cl ... ing-25269/

Pics to follow in a few days!

[benny hedges]

nice one mik
i like the front end & rear sets on the donor bike too - very tasty looking

[sirch345]

Nice one Micky

Chris.

[mik_str]

Jetting update: Bingo!!!!

I pulled the slides out last night and added a 1/16" hole (which raised the area of the 3 existing lift holes (as per Dynojet installation instructions) by 13.6%) and took it out for a ride this morning. I am very happy to report that the end result is sheer perfection. There is no longer any hesitation whatsoever at any engine speed or regardless of how quickly I snap the throttle. IN short, I got exactly what I was hoping for. Mission accomplished!

[tony.mon]

Glad you got it sorted; whoever said setting up carbs is easier than Fi?

[sirch345]

Good to know you got it sorted Micky, well done

Chris.

[mik_str]

Just got in from another ride (am on vacation this week), am up to about 800 miles on the rebuilt lump. The engine is breaking in very well (am always on-off throttle) and is noticeably zippier, responding to throttle with much more intensity. It virtually leaps ahead now, even in sixth gear with the revs down

As well, it has smoothed out considerably. I must admit that I was a bit disappointed with the smoothness initially (had the crank assembly balanced) but everything is falling into place now. At cruising speed (55-75 mph), the engine is uncannily smooth, with no vibration.

My expectations are not only being met, but surpassed (and there is some more improvement to come yet as the miles pile on and it loosens up some more). I'm looking forward to getting it back on the dyno in a few months time to see what the change is...... I am a very happy chap

[benny hedges]

sounds perfect mik.... i want one
need to fine tune the fuelling on mine... still a bit lumpy around 3.5.... i think i just need to lift the needles a touch tbh.
think i'll leave the balancing til i fit the hc pistons, then balance it all up, and the lighter flywheel.
mine does buzz a bit but i thing mostly its cos i have solid ally footpegs with no rubber foot.
there's no vibes on the mirrors like...

post a vid up of it in action bud

[tony.mon]

Keen to see the numbers....

TBH, I expect some vibes with a vee twin, if you want smooth the other engine layouts will float your boat.
You're having better running-in weather than I had when I rebuilt mine over the British winter (admittedly nothing on yours!)- ice and snow- it kept locking the rear when I shut the throttle.
Didn't dare brake!

I always enjoy that period after a big rebuild where you and the bike are getting used to each other again.

So what's next?

[mik_str]

I am a complete neophyte when it comes to electronics. Fortunately, there are others who are not.....

There are some well laid out instructions from a chap named Markus (aka Tweety) in this thread:
http://www.superhawkforum.com/forums/mo ... ter-23088/

Hope this helps. FWIW, my tach is inoperative at the moment although I suspect the problem can be traced to the Yellow/green wire from the VTR harness mating to the blue wire in the SP harness (yet to be confirmed as I don't feel like pulling everything apart at the moment but everything else works so it seems to be the logical problem; anyhow, the actual checking will get done on a rainy day or possibly next winter....)

Hope this helps

P.S. As for being satisfied, I am at the point now where I can no longer afford to pursue the dream/evolution any further; all the relatively inexpensive stuff has been done and any further (significant) mods require more money than I can throw at it...... Besides, it's a street bike, not a racer, and it works very well in its environment

P.P.S. I am still waiting on the mailman to drop off my Mori lower. That will effectively cap off the mods (unless a good deal came up on a lightweight subframe or gas tank...)

[sirch345]

Just got in from another ride (am on vacation this week), am up to about 800 miles on the rebuilt lump. The engine is breaking in very well (am always on-off throttle) and is noticeably zippier, responding to throttle with much more intensity. It virtually leaps ahead now, even in sixth gear with the revs down

As well, it has smoothed out considerably. I must admit that I was a bit disappointed with the smoothness initially (had the crank assembly balanced) but everything is falling into place now. At cruising speed (55-75 mph), the engine is uncannily smooth, with no vibration.

My expectations are not only being met, but surpassed (and there is some more improvement to come yet as the miles pile on and it loosens up some more). I'm looking forward to getting it back on the dyno in a few months time to see what the change is...... I am a very happy chap

Top man Micky, well done somehow I had a feeling you'd get there

Chris.

[mik_str]

The beaaaaaautiful Moriwaki lower arrived yesterday. Now I just need to find a few minutes to install it..... Will post pics when done

[mik_str]

Mori lower on (had to add a few stickers, lol). Behold....