RB Head Mod...

Post by **Indawoods** » 09:37 pm Dec 04 2005

Man... I just gotta say... that's a beautiful thing CC...

Can't wait to get mine back....

canyncarvr · Post by **canyncarvr** » 02:38 pm Dec 05 2005

It's a curious thing...head reconfiguration. I guess it's kind of like swapping different shims around in a valve stack and actually making it work!

The reason I sent my head up to RB was in an attempt to reduce some of the detonation I had after a port job. Yep..completely unfair to ask someone else to clean up a problem that they had nothing to do with...but I did.

No, the detonation problem was not resoloved, but it is considerably improved!

Detonation? Too much compression? Increase the compression to help that situation?

Well..that's a tad on the simple side...but close.

Yep. Like everything I've seen of Ron's work...beautiful indeed. AND it WORKS, too!!

dave04kdx · Post by **dave04kdx** » 05:19 pm Dec 05 2005

What does the head mod do for the KDX?

Yes the head does look good. My RB'd carb looked so nice it was almost a shame to put it back on the bike.

Post by **fuzzy** » 05:48 pm Dec 05 2005

Man, that's some good head...

IdahoCharley · Post by **IdahoCharley** » 09:53 am Dec 06 2005

You may not see the bling when it is installed - but RB's work does get the job done!!

canyncarvr · Post by **canyncarvr** » 01:05 pm Dec 06 2005

Some of this has been around..but this is a good thread to stick the montage in:

More good stuff from RB

re: what does head reconfig do?

From a rider's point of view (known, ridden and heard from others):

The 220 head has some rather common 'defects' in that they vary a whole lot in size (volume). The 200 head is better in that regard. If your 220 head happens to be 20cc when it works better (pump gas) at 18cc, then there's a quick 10% improvement to your bike's performance!

JUST KIDDING!! It's an inside joke about numbers...don't worry about it.

Higher compression in a two-stroke tends to improve bottom end response. Yes, at the expense of top-end in some cases (depends on how much of it you do).

If you commonly ride at higher el., then you need all the static (numerical) compression you can get! If a race-gas mix is your choice of fuel..there's another reason to increase your compression.

There are a couple of whys to increased compression.

But...that's not the largest part of it (sez me). Do some research on 'squish band' and how it works/what it does. Ron reconfigures the squish band to improve all that stuff (that you will read about if you choose to go looking).

A paraphrase from Mr. Gorr (well, it's on his site anyway...don't know that he's the source): It's 95% rider and 5% bike...better make that 5% count!

Sure! You can have fun on your OEM KDX. Fact is, it's not an engineering marvel in the way of cutting-edge wonder. If you're of the group that thinks the front end of the KDX fits you perfectly and a KX frontend is a waste of time and money..then there is likely no reason you should have your cylinder head reconfigured.

It's not about how much money you can sink into your bike..but what works and what doesn't.

Reconfiguring your cylinder head works.

Post by **Indawoods** » 06:07 pm Dec 08 2005

Well Ron recieved my head today, machined it and is sending it back to me tomorrow!

Man...that's quick!

Post by **Indawoods** » 11:03 pm Dec 13 2005

I got the head back from Ron and he has performed MAGIC!

As you may recall the head I bought off of eBay was completely trashed. The guy who took it off the bike was a hack and used a screw driver to pry it off leaving huge gashes in the mating surface. Ron got all of that out as part of the mod and cut a nice anti-detonation ring. I can't wait to try it out this spring....

He is one of the true craftsmen that deserves to be recongnized.

KDX220PHIL · Post by **KDX220PHIL** » 05:03 am Dec 14 2005

Excellent, can't wait to hear how you like it.
What do you figure a used average to good condition head is worth.
I found a buddy selling a 98' 220 head for $20 + $10 shipping.

Post by **Indawoods** » 06:33 am Dec 14 2005

Snag it!

KDX220PHIL · Post by **KDX220PHIL** » 07:25 am Dec 14 2005

Well, I asked him if he would ship to Canada, he said yes.
I asked him how much? He sent me a rude email saying I was too much trouble and that from now on NO CANADIAN BIDDERS!

Here it is if anyone wants it, I would not mention that you heard it from me as I sent a return rude email to him and blocked his email.

.

http://cgi.ebay.ca/ws/eBayISAPI.dll?Vie ... A%3A1&rd=1

It is a little dirty, but the machining would refinish the inside and surface, and the part could be etched to bring back the nice colour. Shops that do iridite plating (the goldish colour anti-oxidant) would probably charge no more than $5.00 to have it etched. I hear you can get similar stuff from automotive stores too.

Ryan · Post by **Ryan** » 09:01 am Dec 14 2005

maybe i will go ahead ans pick it up. can i have you site were you guys are getting your head modd done??

Also i dont need race gas right???

KDX220PHIL · Post by **KDX220PHIL** » 09:15 am Dec 14 2005

http://www.rb-designs.com

I dont think you NEED race gas, but with the increase in compression it will perform much better.

Soemone else can answer that question better, CC?

skipro3 · Post by **skipro3** » 10:28 am Dec 14 2005

Phil,
If you want it, either buy it and drop ship to RBDesigns and have Ron ship it to you, or, if you'd like, ship to me and I'll send it on to you. Let me know if I can help. Heck, if you can't bid on it now, I will and you can send me the money.

KDX220PHIL · Post by **KDX220PHIL** » 11:24 am Dec 14 2005

Thanks for the offer Ski, that is very generous and kind of you. I will let Ryan take it if he wants it. But I will keep your offer in mind

, if you really do not mind.

canyncarvr · Post by **canyncarvr** » 02:05 pm Dec 14 2005

You won't NEED 'race gas' unless you TELL Ron you are going to be running 'race gas'.

The 220 heads vary considerably in volume measurement (said that already). If the head you have happens to be larger than it reasonably should be, you're wasting some 'free' available power. Don't know about the 'much better' part, but a bike that performs well is the sum of all sorts of parts..not all of them great big huge items.

Where head modificaton really helps out is with the folks that ride high on a regular basis. If you have not been above 8000'el. with your bike (nothing special about that number), you don't know what you would be missing. Power! Some of these guys are well above 10k. It gets thin up there.

If you have a question about the process you have in mind for your bike...ask Mr. Black.

Because you asked...Mr. Black's site URL:

http://www.rb-designs.com/

uh oh...I don't guess he likes spam arrest...

Ryan · Post by **Ryan** » 02:13 pm Dec 14 2005

well if you really dont want it phil, i think i will get it. Seems like a good benfit for only $70. I could always use somemore mid and top end. Has anyone done this on a 220? Did you notice a big power differnce? Did you lose any power in some area's? Also will this wear the life of top and botoom end down?? thanks for any help.

KDX220PHIL · Post by **KDX220PHIL** » 02:43 pm Dec 14 2005

Go for it Ryan! I'll find another one eventually.

I believe what CC is saying is if you tell Ron you are going to be running race gas, he would machine the head to support race gas. I think he may machine the surface of the head (among other things) down to decrease the volume of the combustion chamber and therefore increase compression. If you are going to use race gas he would machine it to a smaller volume than if you were to use standard gas as race gas can ignite at a higher pressure than your standard gas.

Someone correct me if I am wrong, or feel free to add to this.

Oh and BTW higher compression will give more bottom end.

canyncarvr · Post by **canyncarvr** » 03:48 pm Dec 14 2005

re: 'I believe what CC is saying is....'

Yanno, I honestly do NOT try to be difficult about stuff. I DO elaborate too often/much..but that in an effort to be clear to everyone reading....

Anyway...what Phil said, including 'among other things'. If you have question of a specific nature regarding your application (as opposed to being merely generally curious), ask Mr. Black.

To address the freak specifically, re: 'Did you lose any power ....'

Compression increase will commonly add to the bottom-end response of things. It will also take away from the top-end of things. It's akin to spark timing in that regard. Advanced spark timing will enhance the bottom-end and be a minus to the top-end.

re: '..will this wear the life of top and botoom end down??'

The fact of the matter is this: ANY increase in power output is going to be at the expense of something. The greater the compression of the air/fuel mixture, the greater the resulting pressures when said mix is ignited. That greater pressure is going to be felt, of course..on the head/cylinder seal, the rod bearings, the piston crown, the piston rings etc. etc.

That is NOT to say an increase in power is a bad thing. You don't see riders scrambling to reduce the power of their machines to enhace longevity, to you?

It's all a question of balance (good album, btw. ..did I say that already?). Any modification can be taken too far. What you're looking for is an improvement to the existing situation..one that will not reduce longevity or reliability.

Take lighting as an example. The oem lighting coil puts out about 45 watts. If you want to run a twin headlamp shell, you will need a 'better' lighting coil. BUT...it is harder for the bike to 'run' that larger coil! You do NOT get SOMEthing for NOthing. So..what's the better option? Taking a bit of power to run the better lighting system or running with less light?

That's a decision you need to make for yourself.

When you find out that adding that larger lighting coil ends up improving your ignition performance, it's all good!

Nothing from RB-Design's is going to hurt your bike. You will be surprised at what the little green machine can do when it's running well!

Cliff's Notes version: Don't worry about it.

KDX220PHIL · Post by **KDX220PHIL** » 04:12 pm Dec 14 2005

I was hoping you would elaborate more!

Myself, I am just curious but I would prefer not to waste Mr. black's time asking unless I was prepared to have the mod done now, and ask here instead. As a machinist, I am very curious of the HOW's to make WHAT happen.
Having said that, I am also very respectful of others work/inventions/discoveries but love to learn about anything related to machining and bikes.
Guess I should buy THAT book.

KDXRIDER.NET

KDXRIDER.NET

RB Head Mod...

RB Head Mod...