Powervalve trimming?

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kdxsully
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Powervalve trimming?

Post by kdxsully »

I’m considering getting a box ‘87. Guy has everything in boxes, and the bottom end is rebuilt already.

Here’s my question. The cylinder is sleeved and needs work. If you bore one of these, do you need to trim the power valves? How much would that cost? Is it better to just resleeve? Should I even bother?

Thanks for any insight on this. I’m almost hoping I don’t end up with another project. :lie:
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Re: Powervalve trimming?

Post by KDXGarage »

OMG. The one on Facebook Marketplace in SC for $900?! :grin:

1986 - 1988 don't have a flapper valve or middle drum / valve, so that would not apply, I don't think.

How bad is the sleeve?? It might can be bored and honed (and ports chamfered).

Hopefully it does not need a new sleeve.
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Re: Powervalve trimming?

Post by kdxsully »

KDXGarage wrote: 09:37 pm Jul 02 2019 OMG. The one on Facebook Marketplace in SC for $900?! :grin:

1986 - 1988 don't have a flapper valve or middle drum / valve, so that would not apply, I don't think.

How bad is the sleeve?? It might can be bored and honed (and ports chamfered).

Hopefully it does not need a new sleeve.
Image

Is this what you saw?

The sleeve looks really good. Half a mm should do the job. I’m just not familiar with the powervalves. Crank was rebuilt, no up and down rod play, and the bottom was already put together. Something stopped this guy from rebuilding though. Did he find another good deal? Are the flywheel magnets thrown? :hmm:
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Re: Powervalve trimming?

Post by KDXGarage »

Same one! HA HA!

Look on eBay at the 1986 - 1988 cylinders. You can see how the holes are a little bit away from the cylinder.

No way I would pay $900 for it. If you decide against it, I will rip it apart (nit pick it to death). If you get it, I will just say good luck! :grin:
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Re: Powervalve trimming?

Post by kdxsully »

KDXGarage wrote: 10:43 pm Jul 02 2019 Same one! HA HA!

Look on eBay at the 1986 - 1988 cylinders. You can see how the holes are a little bit away from the cylinder.

No way I would pay $900 for it. If you decide against it, I will rip it apart (nit pick it to death). If you get it, I will just say good luck! :grin:
He told me 600. I wouldn’t pay a dime over 400 for it, if everything is really there and nothing important is screwed up. Might have to use the ol’ bad flywheel magnets trick.
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Re: Powervalve trimming?

Post by KDXGarage »

You can get one that runs for $1,000.

People have lost their minds on parts bikes. Bike in a box for $900. HELL NO
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Re: Powervalve trimming?

Post by kdxsully »

KDXGarage wrote: 07:30 am Jul 03 2019 You can get one that runs for $1,000.

People have lost their minds on parts bikes. Bike in a box for $900. HELL NO
Not even 1000. And who knows what issues I’ll run into. I respect the rebuilt bottom end, but who just gives up on a project they’ve committed to and buys another bike? There’s a piece of this puzzle missing. I really want to buy it to rebuild it.
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Re: Powervalve trimming?

Post by Molly's 70 »

I'd offer $100 & walk at $150. He can ebay it. I would gladly overpay for a well preserved KDX.
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Re: Powervalve trimming?

Post by KDXGarage »

It needs the forks rebuilt, shock rebuilt, how old are the tires and tubes, new top end AND bore / hone, reeds?
chain and sprockets?
ON and ON and ON

EXPENSIVE linkage bearings?
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Re: Powervalve trimming?

Post by kdxsully »

KDXGarage wrote: 05:52 pm Jul 03 2019 It needs the forks rebuilt, shock rebuilt, how old are the tires and tubes, new top end AND bore / hone, reeds?
chain and sprockets?
ON and ON and ON

EXPENSIVE linkage bearings?
THERE’S that puzzle piece I was talking about. :lol:

You guys are probably right about having to rebuild this stuff. I’m too optimistic in hoping he’s at least done something to it.

Lordy, those linkage bearings.
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Re: Powervalve trimming?

Post by kdxsully »

Update: went back and forth with the poor guy. He won’t budge off of his 600 (he wants his money back). Not my fault he’s knee deep in shitake mushrooms. Oh well. :wah:
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Re: Powervalve trimming?

Post by KDXGarage »

YOU WON!!

I find it REALLY TOUGH to walk away from a bike, but I think you did the right thing on this one.

Congratulations on walking away from a too high price.
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Re: Powervalve trimming?

Post by kdxsully »

KDXGarage wrote: 06:27 pm Jul 06 2019 YOU WON!!

I find it REALLY TOUGH to walk away from a bike, but I think you did the right thing on this one.

Congratulations on walking away from a too high price.
I wish I could post our messages :lol:

He bought a bike in pieces, when I asked if it ran before it was torn down the guy said “PO rode it for years” (likely a bad thing)

He’s a clown. I can’t even confirm that it sparks. He’s bitten off more than he could chew.
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Re: Powervalve trimming?

Post by KDXGarage »

screenshot them. LOL

Bike in a box, $900. Still sounds silly.
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Re: Powervalve trimming?

Post by kdxsully »

KDXGarage wrote: 08:19 pm Jul 06 2019 screenshot them. LOL

Bike in a box, $900. Still sounds silly.
Nahh I don’t wanna put him out there like that. I will say some pretty silly stuff was said.
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Re: Powervalve trimming?

Post by KDXGarage »

HA HA HA HA!! Good enough to make me lough out loud!
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Re: Powervalve trimming?

Post by kdxsully »

KDXGarage wrote: 12:02 am Jul 07 2019 HA HA HA HA!! Good enough to make me lough out loud!
This was the best one - He said there probably isn’t a big market for parts. I said that the flywheels can be sold for almost 200 in good condition because a lot of them break. He responds, “Well there ya go you’ve got a parts bike for 400!”

:toimonster:
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Re: Powervalve trimming?

Post by KDXGarage »

I wouldn't have told him that. You only strengthened is resolve. :-)
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