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Thanks Ben :) great to see you as always.

All :

www.gravesport.com is our parts and accessories branch of the company Coupon code: "r3forum" is always available for parts sales. The airbox kits are in manufacturing. We'll post soon as they are released.

www.gravesracingservices.com is our team direct parts. Specialty bike purchases form our team, parts like Suter, YEC kit parts and much more can be obtained through this outlet.
Thanks for posting this information! :)

Jim G
 

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I want 46hp. Make it happen, cap'n.
Call or email and we can sell you the parts to do yourself and or do the servicing in house. All these bikes and more start right here inside the Racing Services shop where we actively develop every day.
 

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I did some analysis this evening, including a simulation using my modeling software, and it turns out that this combination of airbox mods + camshaft retiming has some pretty impressive effects on the TORQUE curve and on the acceleration and top speed performance of an R3:

First, recall that Ben only gave us the POWER curve, not the torque curve. The power and torque at any rpm are mathematically related via a simple formula:

HP = T x rpm / 5250

which can be expressed also as:

T = HP x 5250 / rpm

I did this transformation in order to get the Torque versus rpm curve. That curve is profoundly interesting. It turns out that even as low as 4500 rpm, the torque is 19 lb ft. More importantly, the rear wheel torque hits 21 lb ft at 7000 rpm AND NEVER DROPS BELOW THAT UNTIL ALMOST 11,500 RPM! That degree of sustained high flat torque "curve" is very remarkable on ANY engine, but even more so on a 12,500 rpm engine. Whoever did the tuning is REALLY good. That says very good things about Graves.

Secondly, the performance improvements that result from this now 46 rwhp engine are pretty impressive. Now, I first modeled my own R3, which is 42 lb lighter than stock, and already has the Graves Cat Elim exhaust and corresponding ECU tune. Then, I imagined adding the airbox and cam timing mods to it, and modeled THAT. Here are the results:


Crusing HP at 60 mpg increased by 2 rwhp

0 to 60 mph time dropped by 0.37 second

Quarter mile time dropped by 0.53 second

Quarter mile speed increased by 5 mph

Top speed increased by 7 mph and was limited, with OEM gearing, by the rev limit

Average rwhp available between 60 mph and 100 mph increased from 39 to 45 rwhp (which also shows how excellent the R3 gearing is: It enables the R3 to deliver an AVERAGE 45 out of its 46 PEAK horsepower within that 60 to 100 mph range! That's GOOD, and a direct product of that sustained torque curve I mentioned earlier.

So, yeah, this Graves combination of airbox mod with camshaft retiming and tensioning is a pretty impressive package.

I predict it'll sell like the 1965 Mustang did for Ford, if Graves prices it reasonably.

Jim G
 

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I PMed Gravesport last evening, and found a reply when I turned on my computer this morning:

"
Hi Jim,

Soon as the airbox mod kit is completed for resale, we will get it on the website and make things available for everyone. The rest of the parts are available now through Graves or Bayside right now. Tuning options will need to be addressed by Chuck and Flash Tune's ability to lock our files like we've discussed in the past. If anything has changed with FT at the product release you'll be the first to know. Cheers and have a great week.
"

To clarify what I think they mean:

The airbox mod kit is being readied for production and sale, and will be added to the Gravesport website when ready.

The cam chain tensioner and slotted (i.e. adjustable) cam sprockets are already available either directly from Graves or from a Graves dealer. (The email refers to Bayside Performance, my nearest and preferred Graves dealer)

Matching tuning files are needed to harvest the benefits enabled by the mechanical changes (the airbox mods, and the adjusted valve timing via the slotted cam sprockets), and the exact tune needed of course varies with EACH of the mechanical changes made (e.g. which Graves exhaust is installed, is the airbox mod installed, and is valve timing changed via slotted cam sprockets?).

But there is a potential delaying factor here: Graves cannot release the tuning files "unlocked", as that would enable anyone to buy a single copy of the tune, and then give it for free to others, resell to others, analyze it and make a "clone" that they then resell, or worst of all, make an erroneous damaging change to it and distribute it, which would harm Graves's reputation. Any of the above actions would either hurt Graves' ability to actually recover the time and money they have invested in developing the products, or would trash their reputation.

So, once they have each of the various tune file versions ready, it needs to go through FTECU's "locking" process, which to oversimplify, targets the tune file to a specific ECU and prevents its loading onto any other ECU. That process unfortunately has been very backlogged at FTECU. This is why it took me 4 months to get the tune file to match my Graves Cat Elim exhaust. (And yes, it was VERY worth it once I got it - see my posted thread on it)

Until those "locked" ECU files are made available, the only other way to harvest the benefits of the mechanical changes is install the parts and get a custom dyno tune done, using either a current other FTECU file and modifying it, or using a Power Commander or other tuning box. The problem with that approach is that it can be expected to be much more costly, and it requires a tuner as skilled as Graves's tuner, and as I pointed out in an earlier post on this thread, the evidence is that the Graves tuner is very talented indeed, so you won't easily find an equivalent.

Unless FTECU makes a stunningly fast turnaround in their backlog situation, we may have to be frustratingly patient. :(

Jim G
 

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Sorry to join in so late. Is this new package up for sale on Graves already and have they sorted out the Ecu Locking process? Can someone please help me with links?
 

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Graves never released this kit for sale. Norton and TST are available (links above), and Spears is another one www.spearsenterprises.com . I have none of the above; instead I have something similar that I made myself before those options showed up on the market. All are visually similar even if not identical; basic analysis revealed which direction things needed to go and obviously we all saw it similarly. I've seen a (realistic) dyno chart from an R3 with the Spears airbox kit and a typical aftermarket exhaust, and it was within a fraction of a horsepower of what my homegrown version did and that's within a fraction of what Jesse Norton published on his website for a comparable setup using his own kit. All will require remapping to add more fuel at high RPM. Bear in mind that the benefit here is above 10,000 rpm, where a race bike lives. There is no benefit, perhaps even a slight disadvantage, below that. If you're not living above 10,000 rpm, don't bother with any of this.
 
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