Big Inlet and Exhaust Valves (+1mm)

[Killerwhale]

Thats interesting....

82Nm of torque = 60.5 ft-lbs which is very very good for 4400 rpm .Mine is only 51 ft-lbs at 4400 as standard,so you're over 18% up.Before you all shout at me,yes,I know we comparing different dynos,but heck,18% is way beyond the realms of plus or minus 2 or 3 per cent dyno disparity.

75Nm of torque = 55.3 ft-lbs. This shows that the mathematics behind the 5225rpm therem holds up.
You've around 55.3 ft-lbs torque and 55.3 bhp at 5225 rpm.

Thanks for posting your numbers.I hope you're able to fill in your torque depression at those revs.

Maybe I'm being way optimistic for my home built motor.


Mark.

If you have not seen it my latest dynochart is under my bike in the member bike department
Guess we will have a lot of comparison charts soon, i have to wait until my mech done all race bikes for 2013 season though...

[johno440]

Hi everyone. I'm been itching to post on my build for some time but was gonna wait till done, but I'll start now

Exact HP and torque figures unknown but aiming for the stars at a 20% increase and will be happy to just reach the moon I will post photos, dyno run sheet and video of dyno run at a later date. I think the head should be something special considering the "guru" doing it I know from prev posts there is a lot of interest in the methods used so very interested myself in path chosen.

Specs to date confirmed with engine builder and what I've purchased:
JE 878 big bore kit (thanks to cobba and fung for putting me onto him )
12.0:1 comp
Tighe billet cams (different specs to Kent to take advantage of the better breathing - different duration & lift profiles)
Carrillo rods
Larger valves and race prepped head (I'll get pics posted of the mods & finished product when possible)
Modified inlet manifolds (again as above)
Lightened crank
Keihin 41mm FCR's
Ramair filter (no airbox)
Ignitech TCIP4 programmable ignition
Takai Super High Output M-Raikou Super Coils coil on plug system (no ignition wires!!) Thanks to Mark Lepore at Takai-Racing (custom built kit)
2 into 1 big bore headers & race can (no DB killers)
+ all the usual balancing and blue printing...

Big thanks to Mark for organising the valves Can't wait to see the finished product and have the shiny little things in my hands

John

[sanddune51]

Johno,

Thanks for posting your specs,that's a pretty impressive list of quality components. If it's all assembled well you're gonna have a pretty special motor that'll stay together.The rods are good insurance. I remember looking at Ivan Tighe billet cam specs,they give lots more lift than is available from regrinds.I've always thought our engines could do with a lot more lift whilst keeping moderate durations for tractability. I have asked Kent cams over here about billet cams for more lift and these run out at about £700 Kinda hard to justify at any level other than for a very serious race bike to antagonise Ducatis. Another factor with agressive cam profiles in the Trx engine is the limiting effect of relatively small cam follower diameter,just 20mm if I recall.

It would be interesting if you could post up some photo's of your ingredient components.

Good luck with the build.


Mark.

[johno440]

Thanks Mark.

Yeah the new billet cams not cheap, $950 AUS as opposed to $520 for built up originals. Only went with the new ones as Dean Tighe advised that idling and slow speeds on the road can damage the build up. Would be interesting to know if anyone has experienced this with the Kent cams.

Exact specs for cam still unknown as cant be finalised till the head is finished with the oversize valves as it all depends on the flow numbers.

Note the engine is going into an offroad racing buggy and will cop quite a hiding, so have gone for the extra insurance with the rods. Also the coil on plug conversion needs min 3 inches above the head to fit on if anyone was interested in them.

Photo's of the bits and pieces will be posted soon.

Cheers John

[Tarwetijger]

Are you back from Cuba yet?

[cobbadiggabuddyblooo]

Hey Tarwet, didn't you say you had revalved a 750sp shock but then found the std spring a little soft??? I was wondering what your weight is as I'm about to do mine and I'm 85kg with leathers on.

[Tarwetijger]

Hey Tarwet, didn't you say you had revalved a 750sp shock but then found the std spring a little soft??? I was wondering what your weight is as I'm about to do mine and I'm 85kg with leathers on.

Yup, that's right Cobba. I'm like 80 kg with clothes on... Leathers could be a little heavier.

[cobbadiggabuddyblooo]

cheers mate...thanks for the feedback

[cobbadiggabuddyblooo]

Thats interesting....

82Nm of torque = 60.5 ft-lbs which is very very good for 4400 rpm .Mine is only 51 ft-lbs at 4400 as standard,so you're over 18% up.Before you all shout at me,yes,I know we comparing different dynos,but heck,18% is way beyond the realms of plus or minus 2 or 3 per cent dyno disparity.

75Nm of torque = 55.3 ft-lbs. This shows that the mathematics behind the 5225rpm therem holds up.
You've around 55.3 ft-lbs torque and 55.3 bhp at 5225 rpm.

Thanks for posting your numbers.I hope you're able to fill in your torque depression at those revs.

Maybe I'm being way optimistic for my home built motor.


Mark.

If you have not seen it my latest dynochart is under my bike in the member bike department
Guess we will have a lot of comparison charts soon, i have to wait until my mech done all race bikes for 2013 season though...

4400 rpm 58.5 ft-lbs
5500 rpm 60.5 ft-lbs
6200 rpm 62.16 ft-lbs / 72Hp
with the best run showing an 86.71hp
http://i393.photobucket.com/albums/pp14 ... rspeed.jpg
http://i393.photobucket.com/albums/pp14 ... torque.jpg
http://i393.photobucket.com/albums/pp14 ... irFuel.jpg
got that same dip around the same area as you too Killer, and the spike in the air/fuel at 5000 may be as you said before about the accel. pump.
Thats my starting point with the FCr's and old 2 into 1 system...
Next step
I'd be keen to see how it comes up just with the Akra system and kent cams as a comparision before any other work internally..


You can see by the dyno sheet the red line is with the small teastrainer bung in the end of the pipe and the blue line was with the open 58mm can (needle jet dropped and how the bike finished off).. and the green as std factory FCR settings and jets... it's still running the std 150 mainjet with bellmouths and Ramair twinsock

[cobbadiggabuddyblooo]

So now I'm sure we've prob all received our valves I was wondering what sort of progress people have made in rebuilds and hopefully some handy feedback for those about to approach doing this modification to their motor.

[sanddune51]

Cobba,

Slow going here. Life and work just seem to get in the way of what I want to do.

Anyway the head is progessing slowly.The porting is all completed and I am in the process of cutting the valve seats with a fabulous Neway valve seat cutter and then lapping the head seat lightly with a "sacrificial" lap.I'm using Engineers blue to verify seat widths before making adjustments. At first "seat cut and lap" the valve clearances were all over the place,many coming in at more than 2.40 mm (larger than readily available valve shims). Having thought greatly about it I'm also sinking the exhausts a little to try and reduce "crossflow" ie. fresh charge flowing straight out through the exhaust.

I'm cheating a little with the bottom cut becuase I'm too tight to buy a 30 degree cutter. I'm using an engineers "half round bearing scraper" and sharpening it frequently with an oilstone.I can achieve flow enhancing radius bottom cut.

It is all taking a long time but I'm striving to the enth degree to do the very best possible job on this head.

All this is happening in the kitchen cos it's freezin in my workshop and anyway the kitchen is the perfect "clean conditions" enviroment







Mark.

[dandywarhol]

These Neway cutters are excellent - even cut through toughened seats for unleaded fuel that a vibrocentric won't touch!

[Dion31]

Hi Mince

I was wondering how you got the indicators to stop flashing so fast when you converted to the LEDs?? Street fighters rule!

Cheers

[fung]

Change the flasher can to an led one

[Mincehead]

Change the flasher can to an led one

Yep, fung`s nailed it. Or, if you prefer use resistors in series, like these or any similar you might find cheaper on Thiefbay etc:

http://www.msa-direct.co.uk/25watt-led- ... istor.html

I cannot access Thiefbay on my works PC so those were the first that came up on a search.
An LED `specific` flasher relay can be bought for around 3 quid in the UK so it`s the simplest and cheapest way to ensure the correct flash rate.
Edit:

Here`s one at £4.62:

http://www.suntekstore.co.uk/goods.php?id=14002138