Thanks Kev, looks like you have beaten the KTM 690 SM on torque:

Performance (homologated) 46,8 kW / 7500 rpm Max. torque 65 Nm / 6500 rpmpls let me know what conversion factor to use for convertion to Nm. Sorry, I can't seem to find this factor on the WWW.

thanks.
marcel

Hey Kev,

If you got enough interest and pre-paid commitment - would you consider putting together a handfull of 'kits'? (i.e. all the bits required + modified barrels etc).

It takes allot of time & effort to get these parts together for a good price, it took me over 4 weeks to get everything as a complete kit. Then you need to machine the cylinder.

I have disclosed all the details where to buy them & what to do, http://www.xt660.com/showpost.php?p=51632&postcount=59
Mine is a once off & other riders would have to sort out their own parts & machining.

If you can find a 660 cylinder, ask Fran (CaptMoto) he might sell his now, he has 2 of them, get it bored & replated, you then do not need to do any machining to the cylinder, a very easy installation. I could not find a 660 cylinder that's why I went for the Raptor cylinder. Just weigh up the cost of buying a second hand cylinder with rebore & replate against a new Raptor cylinder from the states.

Congratulations mate, very good results,would be a good idea to post your new PC3 map for those who wants to go on this direction.Do you thing all these mods without the piston conversion there is a possibility to get closer to 54,55 hp.

I will be able to tell you later today, I have swopped over the XTX cam & running it on the Dyno in an hours time. This will tell me what the gain is with the big bore & calculate the stage 1 cam HP if it was done by it's self.

Final results for the XT660X to Raptor + Stage 1 Hot Cam conversion.

http://i201.photobucket.com/albums/a...alresults1.jpg

A before & after dyno run with just the Raptor 700 Cylinder 102mm & 11:1 piston kit.

http://i201.photobucket.com/albums/a...onlyPeekHP.jpg

http://i201.photobucket.com/albums/a...igboreonly.jpg

The difference between a Stage 1 Hot Cam & a XT660X with the big bore kit.

http://i201.photobucket.com/albums/a...etweencams.jpg

http://i201.photobucket.com/albums/a...HotcamXTX1.jpg

As you can see from the results, the Raptor big bore kit offers a big gain in torque & HP over the standard XT660. Add a stge 1 Hot Cam & you have great mid to top end power, but with a loss in HP & torque low down.

As I have said before big HP does not mean the motor will be good across the whole RPM range, you need to decide how you ride & where you want the HP & torque.

If you ride 80% of the time below 5500RPM then the big bore is the way to go 3 more HP at peak, 3.82 HP mid range with a big gain in torque, if you ride on the stopper all the time the Stage 1 & big bore is for you with just around 57HP at peak.

If you are going to fit just a Stage 1 Hot Cam, you would be looking at around 4.63 HP gain at peak power. But with a loss of 3.98 HP & torque below 5500RPM.

Thanks Kev, what will be your next step? Are you going to try other cams (stage2/3)?

Looking at how much torque you loose low down with a stage 1 cam I am not going to bother trying a stage 2 Hot Cam now, if you want to race your XT then the stage 2 is for you, but not for me. I just want to see if I can get the stage 1 cam to work better low down & will try a few things with it.

I am testing the PVC valve mod at the moment & then working on a cooling mod soon, waiting on some parts to come in.

I want to find a second hand XT660 throttle body & bore it out by 2mm & renew the butter fly, the Raptor boys have shown some gains around 2 HP.

Kev I think I have a spare throttle body from Loz's first engine, as soon as I am fit to use both hands, I'll have a look in my shed and let you know, but I am positive that it was there amongst the spare parts.

Will let you know. Cheers
Fran

oh and I also think I might have a spare soolant hose from the reservoire to the engine which you asked Fosters last week.

what can I say, fingers crossed (should be my motto now :p) :120::merror::088:

Thanks Fran no rush at all one day when your hand feels better, let me know how much you want for it.

I have already bought a hose from Foster Monster today, he will post it off soon for me.

Very very good Kev,at first I�m going to the stg1 mod+Pc3 as i�ve already bought.I thing the loss at bottom rev range doesn�t bother too much as you only fell at city commuting,I use my bike more often for traveling at the twisties near my city and most of the time the bike is reving at mid and sometimes at top end so I thing it will be OK for me.First I will try the maps you�ve send me,thanks for that.and if the the bike doesn�t feel good I will try a custom map at this guys www.spiga.com.br he is is the only one in Brazil that is Dynojet Certified Center can you believe Brazil is so far behind in these things he will charge me R$400 Reais for a custom map almost $230,00 Dolars, too much I thing but I don�t have a choice .Can�t wait for these stuff to arrive here for me.Thanks for these usefull information....:notworthy::notworthy::notworthy:

All fuel maps are in the map section. Once you have your custom fuel map please send it to me & I will list it with all the other maps.

http://www.xt660.com/showthread.php?t=2887

Another XT700 dyno result

http://www.xt660.com/showthread.php?t=6689

A nicely ported Raptor 700 head.

http://i201.photobucket.com/albums/a...vxtx/russ1.jpg

http://i201.photobucket.com/albums/a...vxtx/russ4.jpg

http://i201.photobucket.com/albums/a...vxtx/russ2.jpg

http://i201.photobucket.com/albums/a...vxtx/russ5.jpg

http://i201.photobucket.com/albums/a...vxtx/russ3.jpg

http://i201.photobucket.com/albums/a...vxtx/russ6.jpg

I have to agree, it looks nice, but I would personally not port the head like that.

I never remove the valve guides like that. The valve guide does two things. It aligns the valve to seat correctly and shortening it can cause the valve to vibrate or not align and not seat correctly each time. Then, the guide also helps with the cooling of the valve. The shorter it is, the hotter the valve will run, especially on the exhaust side. So, leaving it stock length also helps to keep the valve to run cooler.

Also, not sure how much you gain by removing the guide form a air flow point of view. I don't think to much, but if the valve does not seat well, you will loose more than what you gained with the little extra flow.

Then there are a few other things I would change, but that is my own opinion and might not be worth the effort.

Kev, that looks shiney and new!

I do agree, the removal of the guides is a bit radical. I would also look into blocking the AIS hole in the exhaust port.

What other things did you have in mind Freez?

I see the Raptor boys are into 3D porting with flow bench testing, high tec stuff if you have the funds.

Kev, I have a slightly different view to these guys.

I believe that a flow bench is a great tool to have, but flowing by numbers is not the way to go.

It is a fact that the heads that make excellent flow numbers on the flow bench do not always make the best HP on a physical engine.

A flow bench for one cannot simulate actual engine conditions and it flows at a constant vacuum. A real engine flow in pulses so there is a vast difference in how air flows under these conditions. Air accelerates, slows down and even builds up in pressure inside a port. None of which can be simulated on a flow bench.

I see that more and more new generation heads are using smaller and smaller ports and when you put these heads on a flow bench, they produce bad numbers, yet out there on the track, they eat the hi flowing heads for breakfast when it comes to acceleration and power output.

I prefer to flow with mathematical formulas and ratios. I would calculate port choke point based on valve diameters and open or close the port to get the ratio I need. Yes, it might cost you flow numbers on the flow bench, but we don't ride flow benches, we ride engines and the air behavior inside and engine is a lot more complex than just flow numbers.

How to correctly gasflow or port is head is not easy and there is only a handful of places where you can learn to do this correctly. It took me years and years to collect information about this subject and I am actually also not sure if my info is correct. You get so many different views. I picked one view and stuck with it, right or wrong, who knows.

he who dares hopefully wins.what a thread

Lost me long ago :tongue3:

For me I know a fair bit about four stroke heads but do not have the actual experience of porting many of them. This is where experience come in, trial & testing over time. I have done many two stroke cylinders & heads over the years.

I do agree making ports bigger does not always produce more power, to gain torque you need velocity as well as volume, altering or adding bridges or ramps in ports will add velocity which will produce more power.

It's all about delivering the correct volume of air at the fasters speed to the engines demand at all rev ranges. Very hard to get right.

When I had my XT head off it was know where as bad around the seat area as the Raptor heads that I have seen.

A few of the local XT guys have approached me to build them a powerful XT motor.

Not sure when this will happen and if they will go through with it, but let's see.

The biggest problem is that these guys are hundreds of miles away from me and getting the bikes to me is costly.

With the initial Xt's I want to try a few different things and for that I need a running bike.

In the next week or so, I will be doing a few raptor heads and I will take pictures of the process and post before and after results.

Can you post the torque & hp readings, even though the Raptor displays quite a different torque & hp curvers on the dyno.

We would be able to see the difference in the gain. My kind of tuning a before & after runs on the same dyno.

Ok, want to see a stock raptor versus my latest one on the same printout?

Wow, I read this whole F'n post. Amazing. I was wondering about the XT motor and the Raptor motor, difference wise. This about sums it up. Only 43 hp on a stocker? That's seems pretty weak. KTM's new 690 claims 60 hp stock. I don't know if I believe this or not.

Anyway, this is why I read the internet forums because of the guys out there who are willing to share their own experiences in modding bikes. Stealers just want you to hand them a ton of cash and do little or no work for you. Real results here and no B.S.

AMAZING WORK.
:kneel:

Thanks mate, thats 57HP at the rear wheel.

I could have done more to the motor but being my first 660 big bore I was taking it moderately, it was a learning curve for everyone. We now know we can get even more HP but have to watch the torque doesn't reduce to much low down.:icon_scoot[1]:

Thanks to Kev
 

Thanks Kev for sharing it all with us. Very very interesting.
I got a lot of pleasure following your different stages of build and modification.
You are what this forum is all about and Capt. owes you a drink or two!..
(Has you colleague got a machine in his workshop to pry apart wallets?)
:smile[2]:

You can say that again TT, Kev is really what this forum is all about. In fact without Kev, there rest of us would just be amateurs with a passion for bikes (the xt ones in this case) and (personally speaking) --->> very little knowledge, however we must not forget that there are other people like Freez that have similar knowledge and skills, and we also have a lot of people that each help individually with their different mods, such as the crash bungs, the belly pans, the tail end mods and more.

Oh and as for me owing Kev a drink, that is also true, but if you were to read all the forum threads from the beginning you will know that I have somewhat contributed to those drinks, but even then, there are not enough "drinks" in this world to repay his dedication and support. Kev just loves to help out of his own kindness.

Thanks for your kind words guys. I love helping others who have the same passion as me, bikes & have always moded every bike I have owned. So all I am doing is sharing my finding with others.

Yes my good friend Kev2 know as KLR on the forum specializes in making laser atomic equipment for scientists. So getting something made or machined usually costs a few beers, or to work on his bikes.

velocidade
 

Hello Kev, I am in Brazil, already did a job that with a XT600E, increase the piston from 95mm to 101mm, I used a Wiseco, was very good, now I have a XT660 and looking at his work, I'm thinking of something similar. to have a Wiseco piston 103mm, that will reach 700cc, or probably use the same cylinder that you used, and decreases the diameter of the cylinder projection for him to enter the engine block. We have not decided what to do, it will be much more difficult because the bike has electronic injection, the other was carburetor. I do not have many resources, require tools that bike is difficult because electronics.
You've already picked up strong in 5th gear to see how much speed until it arrives?
The other that I did, I used a crown of 43 teeth and relieved to spin the engine while maintaining a good torque. I do not know what power it has achieved. She came to 150 km and started to reach 165km under the same conditions. I did nothing in the carburetor, there was no difference in consumption when used in jacobina normal. Consumption of 20km/litro gasolina.Haver� words you do not understand, because I can not speak English, I am translating in Google.Ficou very good at his bike, congratulations. Good luck to you.

Fred.

Hello Fred welcome to the XT forum.

1/ 6mm bigger piston would give nice gain in torque.

2/ 182kph on the speedo.

3/ You needed to change the needle positions & main jets & your XT would have gone much better with the big bore & run cooler.

Found this new camshaft for our Xt's.

http://cgi.ebay.de/Stufe-1-Nockenwel...d=p3286.c0.m14

http://i201.photobucket.com/albums/a...xtx/cdb6_1.jpg

http://i201.photobucket.com/albums/a...xtx/ce91_1.jpg

Dna Filter
 

Hello Kev, thanks for having responded. The 6mm increased XT600E I took the cylinder recamisado, was placed in an oven, very hot after the hole was removed, the piece was machined and put a new hole, was as much torque and the most interesting result is that the bike vibrates less during the journey, it was more comfortable.
The filter DNA has two versions, the 2nd version turns the whole box of the air filter in and works with a reservoir area of screening much more facilitating the entry of air. The 1st version appears fit on the same site of the original, perhaps it facilitates the passage of air. These filter versions of the same quality and efficiency as the original? The filtering of air, if not good, injures more to life, compared to other preparations.
The control valve that you used in your motorcycle was produced by yamaha?
I noticed that you had another command, Tornado, has already been tested?
Here in Brazil is easy, parts for preparation of small type 125cc bikes, 150cc and 250cc, for XT660R has nothing.
With my XT660R the maximum speed was 172kph, she leads.

The best result is by using DNA stage 1 & 2 filters.

These filters last longer then paper filters, the filters are to be cleaned & reoiled to retain their sealing, I do mine every 6 months.

You say control valve are you talking about the throttle body? If so, yes it is a Yamaha throttle body bored +2mm.

You are correct, I run a Power commander PCIII to adjust the fueling.

Hello Kev, all right?
The power commander III, is installed on the bike?
He changes the original information of electronic injection?
I can choose in which RPM I want him to change the injection electronics?
This cam Tornado is good that you showed?
Good luck buddy!

Fred

Right Said Fred....

:pjrlaugh_61OD3G:

I do not know anything about this cam, one thing it is very expensive.

Me being me, I can't leave things alone. So with just over a year & 10000kms on the big bore, she is pulled down again.

Last night I pulled the motor out stripped off the head & Raptor cylinder. I have refitted the standard XT660 cylinder with a ported head. Strip down & reassemble & running 4hours & 45mins.

I will do some work on the head with some different cams to see what we can get out of the standard motor. I have plans for the removed Raptor cylinder & cylinder head, this is the main reason for stripping the motor again.

http://i201.photobucket.com/albums/aa202/kevxtx/a-8.jpg

http://i201.photobucket.com/albums/aa202/kevxtx/b-7.jpg

http://i201.photobucket.com/albums/aa202/kevxtx/c-5.jpg

http://i201.photobucket.com/albums/aa202/kevxtx/d-3.jpg

http://i201.photobucket.com/albums/aa202/kevxtx/e-4.jpg

http://i201.photobucket.com/albums/aa202/kevxtx/f-3.jpg

http://i201.photobucket.com/albums/aa202/kevxtx/g-2.jpg

http://i201.photobucket.com/albums/aa202/kevxtx/i-2.jpg

http://i201.photobucket.com/albums/aa202/kevxtx/j-1.jpg

http://i201.photobucket.com/albums/aa202/kevxtx/k.jpg

http://i201.photobucket.com/albums/aa202/kevxtx/l.jpg

http://i201.photobucket.com/albums/aa202/kevxtx/m.jpg

http://i201.photobucket.com/albums/aa202/kevxtx/n.jpg

The ported XT head that is now fitted, this was the first stage before polishing. The XT's heads are really bad with big steps around the valve seat area that will disrupt the air flow big time.

http://i201.photobucket.com/albums/a...x/P1000073.jpg

http://i201.photobucket.com/albums/a...x/P1000074.jpg

looking good Kev. As far as I can see the JE piston still looks in good conditions, the head too.

The JE piston did develop a rattle at start up for 5 seconds from cold. I measured the cylinder to piston clearance today & it is still well in spec, Kenny did warn me of the off set pin on the JE piston so I knew what the noise was & did not worry to much.