project

motorson said:
From what I have read, being able to do a "stoppy" has everything to do with the center of gravity of the bike being above or below the level of the front axle. Commandos have the crankshaft below the front axle and I assume that the entire center of gravity is around that low as well. Going to smaller front wheels makes it harder to get the center of gravity below the axle but I would not say that corner handling is adversely affected by that necessarily.
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Spot on. Stoppies are a function of the coefficient of friction between the tire and surface as well as the height (and location - forward or aft) of the center of gravity of the bike and rider. This is a text book classic example of "tipping versus sliding".

Older British bikes tended towards lower center of gravity with a roughly 50/50 front/rear wheel bias whereas more modern sport bikes tend towards more bias to the front.
 
i stop shorter on my old Nortons with skinny tires and Lockheed kit w/o the restrictor than I could on dual rotor 120 balloon race tired modern sports bikes on or off track and on or off road. i disdain trail braking but can drag my Nortons down while leaned better than on moderns. The modern hi CoG and front bias is their down fall to keep up with me in turns because as their rears are already unloaded into turns their rear grip becomes less loaded the more they try to put power down in leaned turns, zip splat. I've posted video of me sliding Trixie's locked front powering up, because I don't trust her non rod linked chassis to take the swap ends loads I got on Ms Peel sliding locked tire a few bike length trying and tyring and trying to stoppie a Commando. Only got rear to lift off surface completely but not lift but maybe an inch i could feel bounce back when I let off, mainly because I was unable to stay in seat no matter how back I set with locked arms to prevent it. Light bike and rider on light wheels makes a big help in Whoa right now. I expect even better on Peel when her rear is sucked down and front extended to hit panic stop brakes as both ends should be effective at high speeds till front grips enough to take rear traction away. I will eventually try a steep down hill stoppie to get what may the only time a Commando seen doing one w/o hitting something.

BTW where's our video hit of this big V twin sounds?
 
hobot said:
i stop shorter on my old Nortons with skinny tires and Lockheed kit w/o the restrictor than I could on dual rotor 120 balloon race tired modern sports bikes on or off track and on or off road. i disdain trail braking but can drag my Nortons down while leaned better than on moderns. The modern hi CoG and front bias is their down fall to keep up with me in turns because as their rears are already unloaded into turns their rear grip becomes less loaded the more they try to put power down in leaned turns, zip splat. I've posted video of me sliding Trixie's locked front powering up, because I don't trust her non rod linked chassis to take the swap ends loads I got on Ms Peel sliding locked tire a few bike length trying and tyring and trying to stoppie a Commando. Only got rear to lift off surface completely but not lift but maybe an inch i could feel bounce back when I let off, mainly because I was unable to stay in seat no matter how back I set with locked arms to prevent it. Light bike and rider on light wheels makes a big help in Whoa right now. I expect even better on Peel when her rear is sucked down and front extended to hit panic stop brakes as both ends should be effective at high speeds till front grips enough to take rear traction away. I will eventually try a steep down hill stoppie to get what may the only time a Commando seen doing one w/o hitting something.

BTW where's our video hit of this big V twin sounds?
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This is why I do not do drugs.

In my humble opinion, the above is beyond delusional blathering; defies laws of physics and probably a few natural laws (for good measure) but it does make me smile and laugh out load.
 
the only way I could get either of my Nortons to stop as quickly as this thing does would be to jam a two by four in the spokes!

Or mount a big double disc brake up front and saw about 100 pounds of the bike, that also would do it

Glen
 
I put dual floating drilled rotors and 4 pot toki calipers on the front of my 75 XS 650 (750 kit). Was much lighter than the stock setup and really throws the anchor out. It's almost scary to squeeze the lever.

project
 
worntorn said:
the only way I could get either of my Nortons to stop as quickly as this thing does would be to jam a two by four in the spokes!

Or mount a big double disc brake up front and saw about 100 pounds of the bike, that also would do it

Glen
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I had no problem doing a stoppy on my Norton. You guys are pussies. Sleeved master cylinder and a handful of brake. No problems.


Well, so maybe it helped to hit a stopped car... :mrgreen:
 
In my humble opinion, the above is beyond delusional blathering; defies laws of physics and probably a few natural laws (for good measure) but it does make me smile and laugh out load.
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Yep sir, hold any opinion ya like, I've done what I say and expect even better next time out and look forward to 0-150-0 contests with laughing magazine editors and hot shots on hotest bikes until the smoke clears. You can't believe it, *boy howdy* was I ever surprised but now am so spoiled. Ping me private or start a new subject on impossible Peel performance and me. If your ride can't take a locked front tire for bike lengths or don't have to fast back off brake d/t being thrown over the bars, then ya don't know what ya missing out on, but I sure do. Regardless - if one ain't practiced on panic stops on various surfaces then one is not fully up to what the world can throw at ya. Test this Vincent's modern brakes to the max to know for sure way ahead of time. I get scared braking, but way less on either of my Combats with Lockheed brakes minus the restriction. Just because brake set up is easy to lock up don't mean much for real pull down ability, just smoke and noise and fooled pilot.
 
hobot said:
Just because brake set up is easy to lock up don't mean much for real pull down ability, just smoke and noise and fooled pilot.
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Well that is the point and that is where we see things very differently.

If you locked it up you are sliding (skidding) and lost control since the front wheel has stopped turning whereas if weight were a little higher or further forward you could pull a few more notches on the brake lever for even more stopping power while maintaining control since the front wheel is still turning.

Works for me; works for the fast riders.

No fooling the laws of physics. :D
 
worntorn said:
interesting.
The Vincent oil pump is pretty pathetic by modern standards in that it only moves a tiny amount of oil. It could be that the Hondas experienced a problem due to much greater oil flow of the pump.

Even with the tiny bit of oil the Vincents pump, they seem to run forever with riders routinely clocking 80 to 100,000 miles between rebuilds. The engine in my Project bike has had a few rebuilds and according to club records has close to half a million miles on it!
I suppose the relatively low RPM helps and it could be that the Vincent engine designer, Phil Irving, got the oil to all the right places.


Glen
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Nice build on the Vincent.

I suspect the big difference between the Honda and Vincent in terms of critical oil feed is the diffrerence in rod journals, where the Vincent has rollers and they are very forgiving if there is a temporary drop in flow whereas the Honda rod journals are sleeve type bearings and do not tolerate low oil pressure or no feed.
 
I've put about a thousand miles on it now. A couple of small problems have shown up, one with the rear brake sticking, the other with the hi tech speedo. The sending unit supplied by Dakota Digital quit after a few miles, as did the replacement. The second replacement was tested by Dakota Digital for several hours before being shipped, it has worked fine. Dakota Digital is a great Company to deal with.
The bike is a real joy to ride, so it's time to use it for some serious travelling. During the build stages I didnt give a single thought toward using the bike in this way, so there was really no provision for luggage or mounting. On top of that the wonderful Craven top box and panniers from my Rapide would look bizarre on there, even if they could be attached somehow.

These saddlebags from Cortech fit rather nicely. There is also a tailbag that goes where a top box would. It clips to the saddlebags. Not sure if it will be needed for solo touring.
The saddlebags are expandable so they hold quite a lot. There are outside map pockets, and some luminescent detailing.
I will need to fabricate a snap-on bracket to keep the bags in place at rear. With this frame design there is nothing back there for attachment.


project


Glen
 
Wow, you have done an amazing job. I may have to contact you about building a frame for me when i get a motor for my project that i'm dreaming up. now take those bags off and get riding!!!
 
Thanks Powereng.

The bags are going to be on there for a bit, I ve got about 5000 miles of touring to do with the bike this summer, so they will get some use!

Glen
 
This motor is very healthy.
You may need the bags left to carry clean underwear. :lol:
 
The kickstart is off a Honda cb 750. I bored it out and then machined the vincent spline into it. There are at least two lengths of cb 750 kicker, this is the longer of the two.

Glen
 
Thanks for the nice comments.
I have a couple of paying jobs to complete then hope to build the new motor in February. Also hoping to reassemble the 47 Rapide that lent its engine to the project.
I still need a few things for the big engine, carbs (delorto pumper 40mms ), pazon twin plug race ignition and a timing cover are the big ticket items.

Glen
 
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