Rc45 Vs. 5th Gen Vfr Engine?

[trjerm]

With the exhaust , throttle bodies , injectors and programmable timing maps, I think just the addition of the cams and remapping should make a big jump in your performance.

[CandyRedRC46]

Oh yeah definitely, you are right, but I will be port matching the throttle body boots to the throttle bodies and the intake ports to the boots.

I just do not have the time or money for 4 custom ground cams and engine work. It will happen eventually though.

[trjerm]

CandyredRC46, do you have any dyno sheets on your current configuration and or et's and please post new et's after your throttle body/injector work

[Mohawk]

Here's my 5th gen current setup. intake mods, exhaust, cams & custom tune, std 95rwhp & now 107rwhp.

[BusyLittleShop]

I rode #001 for a while during the break-in and some after that I did not find it to be all that much more pwerful or fun to ride then the Rc30 bikes . Those bikes were tiny and handled so well out of the box .Cost for the 45 was astronmical here in Canada so caution was the name of te game when riding public roads , Mosport was another story.

You rode balls #1 RC45???

Due to Federal Noise regulations all 56 North America RC45 were

restricted to 89 RWHP but if you performed the HRC 3 wire trick there

was an instant increase to full power which is between 108 and 116

RWHP...

RC45 HRC 3 Wire Mod

[CandyRedRC46]

CandyredRC46, do you have any dyno sheets on your current configuration and or et's and please post new et's after your throttle body/injector work

My current personal best et is 10.82 at 127.8 and that was still untuned as my last dyno tune was only for a slip on, motad header and BMC filter. But I will post up the new et's and dyno as soon as they happen. Probably by mid October.

[Mohawk]

Hey CR is that going to be with the RACE module or a before & after ?

[CandyRedRC46]

That will be before and after the Racing module and with and with out any tuning at all. So I am kind of thinking of buying a set of complete heads, and doing porting/milling/cams. Can the heads be swapped with the engine still in the bike?

[Mohawk]

As someone once said pics or its not real, so here ya go.

https://www.dropbox.... 34 55.jpg?dl=0

Dyno chart for your delectation.

https://www.dropbox..../image.jpg?dl=0

Weight is down to less than 205Kg wet (<180Kg dry), with the aid of much titanium & the RC45 BST carbon wheels, the suspension & braking are fully upgraded with Traxxion Dynamics AK-20 cartridges in the forks which give it full adjustment & the lowers are now VTR1000 units, with CBR929 4 pot nissins. CBS is history & the rear now has a Nitron race remote reservoir shock.

All in all my target was to have a two seat bike (my other half likes to pop on the back now & again) that matched the RC45's (which I can't afford) weight & power. And to prove that the VFR800 has basically an RC45 engine with a different internal configuration. I think I have achieved those goals.

Now I'd like to do a top speed run & a couple of track days, to see how well it really goes. I'll see if I can get a magazine interested too.

[CornerCarver]

Nice work!

[CandyRedRC46]

I can't wait to see a graph with the rev limiter raised to 13,000. That bike is still building power at the stock limiter. :)

[Rush2112]

I can't wait to see a graph with the rev limiter raised to 13,000. That bike is still building power at the stock limiter. :)

I'd love to see it go to 13k too... although, I think the 300 rpm bump puts it at 12.5k. May need to do some internal engine component lightening to go higher

[Mohawk]

I can't wait to see a graph with the rev limiter raised to 13,000. That bike is still building power at the stock limiter. :)

I'd love to see it go to 13k too... although, I think the 300 rpm bump puts it at 12.5k. May need to do some internal engine component lightening to go higher

Well, an 300rpm increase equals a 9% increase in load on the rods. The calculation is exponential so a 1000rpm increase would be a 100% increase in load on the rods, they would not survive that for long, which is why the RC45 with a 2mm shorter stroke used titanium rods. The primary reason was that in WSBK rules at the time you had to use standard crank & rods. The race kitted bikes rev to 14,500rpm, with heavy duty Ti rods. As the Ti rods came as standard the std model RC45 had a 12,500rpm redline & the limiter kicks in around 13Krpm. And just in case anyone's wondering, no we can't use RC45 rods as they are a different length, even if you could get some.

So about 500rpm is the maximum Rev limiter extend you could use. IIRC the calculation correctly, it's the extra rpm divided by 100, times the result to get % load increase number, so my 300 rpm is 300/100=3 x3=9%, so 500rpm/100=5 x5=25% increase in load.

So if the various engineers I've communicated with over the years are right, then most mechanical components have 30-40% extra strength factored in, are you willing to push right up to that on a 10 or 15 year old component ? I'd rather not have to rebuild my motor.

The calc for HP is max rpm torque x max rpm / 5252= HP, so mine is 51ft/ib x 12200 (stock limiter) / 5252=118.5hp.

At 12,500rpm, or 300rpm Rev extend, that same 51ft/lb= 121.3hp, problem is torque is actually falling as rpms increase, so it will be more like 50.5ft/lb at 12,500rpm which is 120.1hp. At 13Krpm torque would be down to about 49.5ft/lb which is 122.5hp, do you want to risk hand grenading your engine for 2hp ? I don't !

YMMV

[CandyRedRC46]

Ugh bummer. 12500 will do fine then. :)

[RVFR]

Whoa,  in keeping a thread topic like this alive.    Nice,  gets one thinking here  Ooo.. so maybe my hic up is cams?

Ok who's got the specs for a re grind?  is there other option available in the grind? Reason for asking this is,  I've had my fare share of re caming a many engines, thing is those cams small and Big block chevys,  where here there everywhere, pick your poison.  Just wondering if one had the opportunity here,  what would be a change,  if?