V4S offset triples - school me

Steven31371 said:

It’s the engine in the V4 SL that’s sexy to me, they lightened almost all of the internal rotating assemblies.

Wonder how much that engine is ala cart.

Would be cool to build a super lightweight track bike around that engine…

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TomFoolery said:

Negative. Motor makes too much power for a lightweight bike. It will twist any lightweight chassis in knots. The best lightweight bike on the market today (Kramer GP2) makes 130 hp, so adding another 100 is like stuffing a size 18 foot into a size 6 shoe.

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Steven31371 said:

Pierobahn is making some pretty cool ‘fairly’ lightweight stuff with Ducati engines….they have a race spec engine there now that puts out 225 hp that fits into the Pierobahn Chasis with a finished wet weight of about 325 pounds that has a full electronic suite with anti wheelie etc that they can build to spec….that chasis was made for that motor

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Steven31371 said:

Pierobahn is making some pretty cool ‘fairly’ lightweight stuff with Ducati engines….they have a race spec engine there now that puts out 225 hp that fits into the Pierobahn Chasis with a finished wet weight of about 325 pounds that has a full electronic suite with anti wheelie etc that they can build to spec….that chasis was made for that motor

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brad8266 said:

That’s lovely, can’t race it in most race orgs, it’s too light. I guess the race class will matter but a 225hp bike isn’t gonna be running in mid/light weight class.

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TomFoolery said:

Is it a real product that is actually 325 wet and they have sold it to real customers? Or is it vapor ware / concept?

OK yes I am a kramer fanboi, but however even objectively speaking, Kramer is pretty much state of the art in today's tech for lightweighting. They use a ton of 3d printing and the gas tank/rear subframe being one unit is key for the lightweight along with material choice. I would be surprised and very interested if someone can outdo Kramer and actually deliver a real product that has been track tested and anything remotely close to affordable money (meaning, not some one off multi hundred thousand demonstrator but a series production motorcycle you can buy for 40-50k or under).

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Steven31371 said:

The Tamburini T12 is a pretty sexy bike too.

But those Kramers are just built sooo well. They even go the extra mile to make them as robust in a crash as you can hope for and made everything modular and cheap to replace.

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TomFoolery said:

Is it a real product that is actually 325 wet and they have sold it to real customers? Or is it vapor ware / concept?

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Steven31371 said:

So apparently these are designed SPECIFICALLY to help prevent pumping of the rear end…(wait, that’s sounds funny lol) on exit.

These links reduce rebound by about 50% thereby reducing rear end pumping on exit.View attachment 39800View attachment 39801


Cycler, a member here can get them for a good price, he also got this info from the manufacturer, which lines up with what Bruce Wayne was saying.


“ As for pumping you will always have some with stock
linkage. Those bikes have so much power that taming it
completely with a sock link is impossible. the main thing is
rebound speed caused by link. Linear link evens out those
we reduce the progression by over 50% on those from
stock. great improvement on tire wear, drive out of corner.
side edge grip, easier tire temp management and makes for
more consistent lap times.”

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Steven31371 said:

So apparently these are designed SPECIFICALLY to help prevent pumping of the rear end…(wait, that’s sounds funny lol) on exit.

These links reduce rebound by about 50% thereby reducing rear end pumping on exit.View attachment 39800View attachment 39801


Cycler, a member here can get them for a good price, he also got this info from the manufacturer, which lines up with what Bruce Wayne was saying.


“ As for pumping you will always have some with stock
linkage. Those bikes have so much power that taming it
completely with a sock link is impossible. the main thing is
rebound speed caused by link. Linear link evens out those
we reduce the progression by over 50% on those from
stock. great improvement on tire wear, drive out of corner.
side edge grip, easier tire temp management and makes for
more consistent lap times.”

Click to expand...

Steven31371 said:

So apparently these are designed SPECIFICALLY to help prevent pumping of the rear end…(wait, that’s sounds funny lol) on exit.

These links reduce rebound by about 50% thereby reducing rear end pumping on exit.View attachment 39800View attachment 39801


Cycler, a member here can get them for a good price, he also got this info from the manufacturer, which lines up with what Bruce Wayne was saying.


“ As for pumping you will always have some with stock
linkage. Those bikes have so much power that taming it
completely with a sock link is impossible. the main thing is
rebound speed caused by link. Linear link evens out those
we reduce the progression by over 50% on those from
stock. great improvement on tire wear, drive out of corner.
side edge grip, easier tire temp management and makes for
more consistent lap times.”

Click to expand...

brad8266 said:

Not quite buying that the linkage is the only solution for rear pumping. Stock the rebound is too fast, especially if you run any decent pace on a track (street riding is irrelevant). The instability and fast rebounding was solved with simple shimming when I serviced the shock. Rebound is neutral while I’m at high lean and it’s a little slow on corner exit and straight line (I tune the suspension for while leaning/maint throttle). Point is you don’t need a linkage to solve for pump or fast rebound. There are cheaper and easier ways to do it.

Not to say I wouldn’t be open to trying a linkage to see what it would have to offer vs stock on a bike that is already dialed in well. Anything to help driving out stronger is a big help.

one thing many forgot to do on a bigger bike is to not run a standard race line but instead square it off quickly/late apex to get the bike picked back up earlier and take advantage of the power. The earlier you pick up a liter bike the better. There are of course lots of corners where you are better taking the standard race line however.

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rac1ngsnak3 said:

Exactly. He’s wanting to ride the 200 Hp V4 like 130 hp Kramer (which rides like a 250 2-stroke). It won’t work. It requires different lines which I believe was touched upon in a different thread by Tom or Steven that talked about swingarm pumping.

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TomFoolery said:

Yeah, I just started riding and the Kramer is what I learned on, haven't ridden anything else. Freaking ........

Focus on your street 959 and leave this thread to people who know a thing or two about track riding. In fact, try to stay out of the v4 forum till you actually own a v4. Want the entire forum to put you on ignore? Take a hint .......

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rac1ngsnak3 said:

Exactly. He’s wanting to ride the 200 Hp V4 like 130 hp Kramer (which rides like a 250 2-stroke). It won’t work. It requires different lines which I believe was touched upon in a different thread by Tom or Steven that talked about swingarm pumping.

Click to expand...

TomFoolery said:

Yeah, I just started riding and the Kramer is what I learned on, haven't ridden anything else. Freaking ........

Focus on your street 959 and leave this thread to people who know a thing or two about track riding. In fact, try to stay out of the v4 forum till you actually own a v4. Want the entire forum to put you on ignore? Take a hint .......

Click to expand...