Duncan PC2000 Cylinder Question

[danhung11]

I got my new motor last night and pulled the head this morning...

My question, was there a sleeve in these motors? I thought they were cast, then nik'd. The bore is 69.50, matches what is etched on the bottom of the intake side.

Comments please...

http://i223.photobucket.com/albums/dd228/danhung11/207b2028.jpg

Thanks,
Dan

[K-Dub]

2000 and 2001 model cylinders had a steel sleeve. Then 2002 and after they where cast. You either got a early one or a repaired one. 00 and 01 cylinders starts with ID#PC-20, 02 and after start with ID#PC-22. Here is a link to DRI's page about the PC2000.

PC2000 (http://www.duncanracing.com/TechCenter/general%20pc200_250r_11-02.pdf)

[danhung11]

Thanks for the info K-Dub. I've read that before, but it's one of those things that really doesn't stick until you have one of these in your garage. I am shocked how big the top end is in size compared to the ProX topends. I have a CT310 ProX next to this motor, and it's significantly larger. I'll have to take a picture with a coke next to them so folks see how large it really is.

Another question... I noticed in the picture that the piston top looks very good, but I do plan to replace it with a fresh piston kit. Do you see that black stuff down on the ports in the picture I posted? Is that common in these motors?

I will say, I am very pleased with this motor - just need to freshen it up with new piston and ring set. Excited how this thing stacks up to the 310 and 330... ProX's.

Dan

[C-LEIGH RACING]

It is right healthy looking & I like the placement of those head studs. Plenty of meat between the bore & those thread holes.
Neil

[rustyATV]

I was TOLD that the early iron liner cylinders had problems seizing above the exhaust port. The design solution was to go to the nicasil liner, but for the iron cylinders in the field the fix was to carbide impregnate them.


Originally posted by danhung11
Thanks for the info K-Dub. I've read that before, but it's one of those things that really doesn't stick until you have one of these in your garage. I am shocked how big the top end is in size compared to the ProX topends. I have a CT310 ProX next to this motor, and it's significantly larger.

I suspect Duncan uses the same casting for all of their engine kits, 265 to 340, is it?

[danhung11]

This is weird, I think this cylinder's been repair at some point or another. The serial number is PC22114 with a 5/2003 etched date. I am unsure why there is a sleeve in it, since it was casted after January 2002. I'll need to call Loren on Monday and see what information he has on before ordering my piston kit.

Thanks for your helps guys.
Dan

[red88r]

Originally posted by danhung11
This is weird, I think this cylinder's been repair at some point or another. The serial number is PC22114 with a 5/2003 etched date. I am unsure why there is a sleeve in it, since it was casted after January 2002. I'll need to call Loren on Monday and see what information he has on before ordering my piston kit.

Thanks for your helps guys.
Dan

That very well could be. If the cylinder wall was damaged too bad I don't know if they can be re-nikasiled or not. We never had to work on our 265 or 340 so I know they are both original besides a fresh piston once and awhile. A sleeve may have been put in yours to save the cylinder.

[rustyATV]

How much do you want to bet they could have just bored it out to a 275 instead of going through the trouble of sleeving it?

[danhung11]

Originally posted by rustyATV
How much do you want to bet they could have just bored it out to a 275 instead of going through the trouble of sleeving it?

Based on the etching under the intake side, it's at the 69.5 bore, but there is a sleeve now. So at some point, it had to be bored out large enough for the sleeve and then rebored to tje 69.5mm. I'm crossing my fingers that it is still nik'd. You know how I can tell? I still see the honing crosses in the sleeve.

It was too good to be true, I didn't even think to question the seller since it all looked so new.

[rustyATV]

Originally posted by danhung11
Based on the etching under the intake side, it's at the 69.5 bore, but there is a sleeve now. So at some point, it had to be bored out large enough for the sleeve and then rebored to tje 69.5mm.

Oh, it's a 275cc jug; was assuming everyone has a small 265, like me :( . But my point was that they might could have gone to a larger size and re-nikasil'd the jug instead of going back to the original size. For instance, years back I looked into buying a powervalved pro-cross that started as a 265, but the owner bored to 295 because they found it had enough port area to support it.


Originally posted by danhung11
I'm crossing my fingers that it is still nik'd. You know how I can tell? I still see the honing crosses in the sleeve.

Personally, I'd be skeptical that it's nikasil'd. I asked about doing that to an iron lined cylinder, once, and was told it doesn't hold as well to iron as it does to aluminum. Carbiding is pretty effective, though; I've used it on my cylinders and the cross hatching lasted through a few pistons.

http://www.bore-tech.com/carbidebore.htm


Originally posted by danhung11
It was too good to be true, I didn't even think to question the seller since it all looked so new.

I wouldn't sweat it if there isn't any Nikasil in there; that's just one feature of these cylinders. You still have the powervalve, the porting, the heavy casting, etc. But if you do talk to Loren, you might ask how large you can bore that jug if you want to go back to Nikasil at some point; looks like there's plenty of material left on there to do it, though the skirts will probably limit you. Be prepared to have to explain that to him; he can be a little argumentative when you have an idea.

[danhung11]

Visited with Loren today, based on my conversation with him we agreed that it's strange to see this sleeve in here and being bored out to a 69.5mm bore. He did not do it, and the buyer from a buyer that I picked this up from swears all the work was done by Duncan. I am not sure why anyone would more it out to the max. In looking at the walls, it doesn't appear to be coated with anything. He offered to inspect it basically free of charge since I just bought it. Kind of erked a little bit, but I guess it's worth sending off to make sure it's perfect seeing how good of condition this top end is in, I'd hate to ruin it and have to resleeve it. The walls look good, just hate taking chances with it.
I guess what's nice about these cylinders is the engraving on the intake side. I gave him the serial number, and he basically told me everything else it said on it... it's ported perfectly for my application, it will be mated to one of my PT mid range pipes.

I'll see what he says, even if I had to drop another chunk of change - it'd be worth it with peace of mind.

Thanks for your helps guys, I appreciate it.

Dan

[TLR-Online]

I'll see what he says, even if I had to drop another chunk of change - it'd be worth it with peace of mind.

I feel the same way! There is nothing worse than riding around wondering constantly if your engine is gonna blow up!

Hopefully everything turns out ok, keep us updated :D

[rrguy]

That one came with a pyramid valve? Something I wanted to try out. Yeah I really wanted to bid on that one lol the more I looked read an listened I was dang sure Loren was going to deliver it to me himself. lol Still Probably A great motor for a good price Yet Don't blame yah for being a bit errked.

I wouldn't have sleeved it but some will just cause they feel if they seize they can bore an throw in next size piston.

Ironic how I know people who just ride never worry about anything doing just min maint. An some of us dig into things an just replace parts to be sure while that one guy just keeps riding lol

[danhung11]

Yes, it has a nice pyramid reed valve in there. PM me if you are interested. I've always been a precautionary type of guy, no sense in taking chances then wind up learning a hard lesson in the end. Don't get me wrong, I'm estatic for what I paid for the complete motor, couldn't get this topend for even what I paid. The seller is a good guy and we've been in communication, he provided lots of pics and even a video. It's one of those things where you don't dive into all the info out there on the web unless you have one in your hands.

[danhung11]

Well, I got some spare time tonight and pulled off the top end, there is a sticky sludge in the jug inself, and also the bottom of the piston is covered. See the crank tins and rod, appears to be some type of oil, etc. Any ideas here? Never seen this much sludge... :mad: Also, what rod is this. One side says Pro Series, you can make out the numbers. Let me know what you guys think,

Thanks in advance!
Dan

http://i223.photobucket.com/albums/dd228/danhung11/100_1931.jpg

http://i223.photobucket.com/albums/dd228/danhung11/100_1932.jpg

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http://i223.photobucket.com/albums/dd228/danhung11/100_1936.jpg

http://i223.photobucket.com/albums/dd228/danhung11/100_1937.jpg

http://i223.photobucket.com/albums/dd228/danhung11/100_1938.jpg

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http://i223.photobucket.com/albums/dd228/danhung11/100_1942.jpg

http://i223.photobucket.com/albums/dd228/danhung11/100_1943.jpg

http://i223.photobucket.com/albums/dd228/danhung11/100_1944.jpg

http://i223.photobucket.com/albums/dd228/danhung11/100_1945.jpg

http://i223.photobucket.com/albums/dd228/danhung11/100_1946.jpg

http://i223.photobucket.com/albums/dd228/danhung11/100_1947.jpg

http://i223.photobucket.com/albums/dd228/danhung11/100_1948.jpg

http://i223.photobucket.com/albums/dd228/danhung11/100_1949.jpg

Here's a video of it running, it sounds real tight and clean. The head was definitely cleaned off seller before it was put back on the jug.

http://www.youtube.com/watch?v=JpQJj3oVmRs

[danhung11]

You guys think this could have 25 hours on it? Seems like a bit more, also appears their is a hairline crack on the innercase..

Up for auction is a spectacular 1987 TRX250R longrod motor that has a Duncan Racing/Paul Turner PC2000 275cc powervalve cylinder and head, newer OEM Crank, Duncan Pyramid Reed Valve, Hinson Racing billet clutch basket and billet ignition plate. The stator has been re-wound for high output lighting systems by Ricky Stator, and it also has a new Hinson Clutch. Duncan Racing did ALL the work on this motor, and it has no more than 25 hours on the complete re-build! Here is the info on the PC2000 cylinder: http://duncanracing.com/buyersguide/hondatrx250r.html#pc2000 the cylinder kit alone is $1795!!!!!!! This motor will also come with a complete wiring harness and regulator that is set up for the high output re-wound stator.

I tested this motor on my property and it makes incredible power and runs perfect. Here is a video of the motor running:

http://www.youtube.com/watch?v=JpQJj3oVmRs

The bore measures 69mm, which is the first/original bore on these cylinders. It has no case damage at all, the case saver studs are intact, and the original exterior paint is in great condition. All seals and gaskets were replaced when it was re-built and it leaks no oil at all. This motor shifts perfectly through all 6 gears and the clutch is new. I will soon have the 37.3mm Keihin PJ carburetor that was paired to this motor for sale in another auction.

This motor is currently set up with a high compression dome to run on race gas only, preferable C-12. You can buy the pump gas dome from Duncan Racing if you do not want to run race gas.

[K-Dub]

No idea on the sludge, unless its from the type of oil he use in it. Defiantly looks to have alot more time than 25hrs to me. Iran Honda 2 strokes for whole race season and practices on 93 octane pump gas and Yamalube look cleaner than that at the end of the year. But I guess it all could be from a cheap premix oil or the like.

[C-LEIGH RACING]

By the looks of the build up in the crankcase & in the cylinder, it has got to have more than 25 hours on it & + was probably a lot of slow riding & the PV closed.
That build up is exhaust blow by. Some of it came in past the rings & some was from port linking around the machined area on the side of the piston.
Any time you see black under the rings instead of all on the top of the piston, it comes from combustion pressure at spark being blown past the rings. A good part of it is from the machined area & exhaust being blown back down the transfer ports.

That engine is as bad as I've ever seen & it still be running. Must have been a bunch of puttering around at low rpm & the pv closed.
Neil

[Langbolt]

What is the Number on the top of the Piston ??? I'm wondering if it's a YZ Piston....hense the use of the spacer plate.

If it were a '87 style Honda piston it wouldn't need a spacer plate unless the rod is much longer.

As for the rod...It's an IMS rod for the '87-9 Honda TRX 250R

http://www.duncanracing.com/mm5/merchant.mvc?Screen=PROD&Product_Code=42-2204

That's from Duncan's website

:devil:

[C-LEIGH RACING]

Those old IMS Hot Rod replacement rod kits were the best you could buy at that time, then they just went away, couldnt find them anymore.
Come to find out, Hot Rods was making them the whole time & when you couldnt find them anymore, it was because Hot Rods & IMS parted ways.

The new Hot Rods kit not the same though, quality just not the same as the old IMS.
Neil

[danhung11]

Thanks John and Neil! I, too, was thinking way more than 25 hours on this topend. Neil, do you have any comments on piston wear, specifically the wear mark almost looks closely to failure. I'm glad I took it all apart. Also, can you pm me your email address?

Thanks,
Dan

[C-LEIGH RACING]

Piston wear looks pretty much normal & if you look close you can still see some machining marks on the lower part.

Now, if it realy was only 25 hours running time, theres some problems some where cause it is way to much. If that is the case, could have been a dirty air filter or it sucked up fine dirt,,,,HO wait, did it have a K&N filter, that would explain it.

Burn pattern looks good on piston top, but all the burnt gunk everywhere in the cylinder & bottom end that would worrie me.

Check the small hole in the cylinder where the pv valve gets its pulse from, sometimes that will plug up & then the valve cant work & it stays closed.
If that valve dont open, it could cause that gunk build up & if the pipe build was way off or plugged up for some reason, that could cause it.
Neil

[rustyATV]

Are the cylinder skirts all from the iron sleeve? No aluminum? Hard to tell.