Dakar Dazed II - the return! Part 1: Project LC4-50

Yes - the idea is not to try and run it at maximum power and the higher rev limit, it was just an experiment on John's part to see what could be achieved... BTW. it's managed 47.1bhp @ 8260rpm now!

John will be along shortly I'm sure with video and graphs and the such like to explain the technical details more fully...

As for the torque - the original figure has been adjusted btw. a mistake in the original interpretation of the figures - so it's not as high as the 690 (and let's face it, it shouldn't have been really?!) so the 690 gearbox isn't going to be troubled by it...

Once we get the graphs, we can properly compare how the torque curves are between the original and 450cc versions - but certainly the torque from the new engine is very consistent from 3500rpm onwards...

Again, John is your man for the real nerdy stuff!

Jx

:eek1

Next thing you know you will reach the same power as the stock 690

Heh heh - knowing John, I think he's just 'banking' some numbers, as I know he intends to put a stock KTM 450 RFR on the dyno in the next couple of weeks ;o)

Of course we know that KTM tried this route before deciding to go with a new engine design based on the SX lump - I guess if you are chasing ultimate horsepower there is going to be a limitation with the over-square design? - however, for anyone else, I think the benefits of retaining the stronger bottom end of the LC4 makes a lot of sense - especially for a privateer on a budget?

It will be interesting to see how far off the [standard customer version] 450RFR we are for sure!

Jx

Curious also what the weight differences are...

I can tell you that John's LC4-50, with all his crap (sorry, I mean 'tools and spares') fitted, plus half full tanks weighs in at 147kg...

Jx

Thats not "crap", I carry an extensive spares selection, and on the Tuareg sold the KTM fuel Pump assy, spare fuel injector, lent my jump leads and lent all my roadbook and ICO's to a less fortunate rider, Roger Hawkins(aka SergeUK).
So theres a method in having the mothership fully loaded, it pays for my rally as the week goes on, and comes back a lot lighter!!!

Hee hee - very true... all you need now is an ice-cream van tune playing as you ride along ;o)

Jx

The LC4-50 on an initial run after remapping the FI, and increasing rev limiter to 8800 RPM.
Check out the fully loaded throttle at 22 secs, no sparing the new motor, she is definitely run-in now!!!!!!!

VIDEO

More to come later.........

As a side note we have had DEP Pipes, in the UK, make us 2 pre-production silencers, one with spark-arrestor, one without.
We used the one with the arrestor for dyno, and the production ones will have a carbon heat shield at the rear to protect soft luggage.
Another variation we tried was to advance & retard the ignition by 1/2 degree, but no increase in power was observed, so we put it back to OEM settings.
Off out for a spin on the road with it this morning, to try the "seat of the pants" dyno for myself.

My 690 in RR Evo 2 guise weighs 170kg with 9 l of fuel in it. Its got gravitas...

This is fantastic news Jenny!! Time for me to start shopping for a KTM 690 Enduro I guess! Obviously times are early, but is there any indication when a package would be available for sale to the regular ADV'er?

A "domestic"

Domestique sound moar better.

Kits available from June, £3800 plus taxes(if in EU) & shipping, will consist of crankshaft assembly, piston, rings and gasket set.You will have to send your own balancer to be machined down, or we can supply one already done.
ECU's can be sent by courier to be remapped onto Position 3 on the mapping switch, so you still retain the 690 ECU settings

John sent me a coupe of print-outs from the first dyno test...

This is the stock KTM 690 Enduro - 40,000 miles so nicely bedded in!


Max figures for the 654cc bike are: 59.1hp @ 6843rpm and 46.4lb/ft torque @ 6250rpm.



The first run on the dyno for the LC4-50 conversion produced this in comparison:


Max figures for the 449cc bike are: 47.1hp @ 8261rpm and 33.7lb/ft torque at 6811rpm.

Of course max figures only tell part of the story... what is clear from the notation on the LC4-50 chart is that there is a nice level* torque curve from around 3800rpm right up to the rev limiter, with no real drop off - indeed 82% of the maximum torque is available pretty much everywhere, with the mid range 5000-7000rpm following a similar curve (albeit with less overall torque) to the 690 engine - which is why I'm sure everyone who has ridden both says the LC4-50 still 'feels' like a 690 in the way it delivers it's power.

*Yes, there is a slight fueling glitch at around 4800rpm on the first run... Despite the dip in the graph, John says that in reality, a seat-of-the-pants road test revealled it was barely noticable... nevertheless, this is being sorted with a second dyno session tomorrow (Friday 18th April) once the custom map has been tweaked by Dave at DWR.

So in conclusion, the curves are broadly similar, albeit with around a 12hp reduction for the LC4-50 at any given revs (and similarly a deficit of 12-13lb/ft torque) - to put that in perspective it's around 20% less power from 30% less capacity - so I'd say that is pretty efficient all things considered! - and ultimately the numbers for the LC4-50 are towards the upper level of what you can expect from a similar capacity production 450cc enduro bike engine...

Perhaps most importantly, the mid-range is particularly strong and level (which is what we want for a rally bike) while there is still plenty of torque available at the higher revs even if we decide to chase maximum power at the top end...

Sweet!

Jx

OK everyone, a quick wrap up of this thread, in preparation for part 2 of the Dakar Dazed II project - actually getting out and racing the LC4-50!

So John and Martin went back to DWR on Friday, and it was indeed a 'Good Friday' (see what I did there?)...

While in Tunisia we had speculated what might have been the cause of the rough running at certain RPM (albeit while running a guest-imate fuel map built on the fly by Martin Wittering of Torque Racing).

Turns out that fitted with the open airbox lid and free-flow filter that works so well to uncork the stock 690 capacity - the LC4-50 was indeed getting simply too much air for the reduced 450cc capacity to ingest properly, even with a piston profile that closely replicates the draw and velocity of the 690cc version - and it was effectively choking itself on too much air and fuel...

So John elected to fit a stock 690 airbox (and filter) just to see the difference, and sure enough, the result was an instant 1.5hp gain!

A little more tweaking of the fueling, together with fitting the alternative DEP silencer (without a spark arrestor fitted), and the ultimate power and torque figures are below:



Just shy of 50bhp from 450cc! - together with another couple of lb/ft torque from the dyno session last week! - interestingly you can see the effect of the reduced airbox, that the max power and torque is more, and at around 500rpm lower than last week...

With the step in the curve smoothed out too, we now have a very strong engine, with a broad and level torque curve, coupled with some very credible top end power as and when it's required!

Excellent result and top marks to all concerned - John Mitchinson (Rally Raid Products), Martin Wittering (Torque Racing) and Dave Woods (DWR Racing).


With the engine and fueling finally sorted, it was time for John to swap a few bits around prior to the first real endurance test - yep, not only will I be racing the LC4-50 at the Hellas Rally next month, but I shall be riding it all the way from the RRP HQ in the UK, via Austria and Italy to Greece - before racing the Hellas (I'm #155 btw.), then riding it all the way home again!

The intention is to prove it's ultimate reliability, and illustrate that we have finally achieved what we set out to do 18 months ago - which was to create effectively the 'ultimate privateer rally bike' - something you can realistically ride to an event, compete on, and ride home - with minimal preparation and servicing throughout...

SMC wheels fitted for the run down through Europe... just for the hell of it really!


John out testing a new headlight set-up at the weekend:



So to coincide with my visit to Rally Raid Products on Tuesday this week for final prep prior to my departure next weekend, I'll be starting a brand new Dakar Dazed thread here on ADVrider - featuring regular updates as we ramp up towards the Hellas Rally and beyond... then soon after we hope to be able to announce the 2-bike Dakar team for 2015.

Thank you all for staying with us on the journey so far, and welcome at last, to chapter two!

Jenny xx

fantastic news jmo. looking forward to hearing all about it.

Good stuff!

Thanks for the updates - I'm in for Round #2.

Wow... a lot of miles to Hellas!! Which roads should you take here in Italy?