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-   -   Engine rebuild: what to buy and where (https://www.horizonsunlimited.com/hubb/yamaha-tech/engine-rebuild-what-buy-where-78159)

beagle scott 19 Sep 2014 10:16

Great home work :thumbup1: So I read up on your carbs wow that looks like a lot of work from the carbs BACK ( air filters ect ) tonight as I put my bike into 2nd and it was I was still able to hold the front wheel in the air I was wondering if this is only a fraction of what it could do with 660 carbs ? My bike has never done this before and I need to know if this is how it should have gone before I hotted the motor up or is this how yours preforms ?? sorry for :offtopic:

jjrider 19 Sep 2014 12:09

Quote:

Originally Posted by Zergman (Post 480097)
jjrider, I would understand that if it was just the seller, listing a Grizzly pistons and claiming it will fit an XT, but is the manufacturer lying too?

When checking the part number I found this on the Wiseco web page:

4607M09800 Product Detail Information - Wiseco Piston Inc.

Check "Applications" section. It says:


Yamaha YFM600 Grizzly (1998 - 2001)
Yamaha SRX600 (1984 - 1996)
Yamaha XT600 (1984 - 1996)
Yamaha XTZ 600 Tenere (1984 - 1996)

I can measure the piston once I receive it.

There are 2 grizzlies, one earlier for a couple years were they obviously used the XT's piston, the later is with the Raptor, which is the version I've been working with and measured at home. Forgot about that other one. Hence the difference.

Zergman 19 Sep 2014 13:39

jjrider, so your verdict: it should fit, right?

Scott, it's a bit of work, yes. My "setup" isn't completely finished yet though. It might change over time...
Well, if I tried hard I probably could do a wheelie in a 2nd gear (not that I'm a pro at wheelies), but bear in mind the sprocket sizes, engine wear, etc.
My sprockets are 15 in front 40 in the rear. So it's quite tall gearing.
Also my engine is (or rather WAS :innocent: ) pretty worn (see piston ring gaps...), so it didn't have much compression and not much torque to pull a wheelie.

But anyway, considering the costs and benefits, I still would do a conversion.
Now I'm wondering about flatside Keihin FCRs or Ninja fuel injection kit... MAYBE one day, haha!

jjrider 19 Sep 2014 20:00

Ya, it is right, I had the later version in my head which isn't the right one. I used it in a hybrid motor with a 660 bottom and the old XT topend.

There was a guy around here that could wheelie his moped, looked like it had been wiped out on a few occations.

beagle scott 21 Sep 2014 10:32

WOW thats some balance ! no I cant do that I was talking power stands not on the ballance point I can power stand up hills well ( on my fuel injected 450 Sherco ) but not on the road like that chap :clap: I'm just trying to get a comparison of HP as I have never ridden another XT 600, I'm running 16 45 gearing for memory, so that sounds close to yours. bier Thank for that !

Zergman 26 Sep 2014 08:06

The shiny bit (the piston) has arrived. I'll post the pic later on.

The instructions added only say what piston ring gaps should be, but no info (or I'm too blind to see) on what should be the piston-cylinder clearance.
Anybody knows that?

Bobmech 26 Sep 2014 11:37

The Yamaha shop manual says piston to bore clearance should be 0.045 - 0.065 mm, or 0.002 - 0.003 in, with a limit of 0.1 mm or 0.004 in.
But if you're using a non-OEM piston, then I would check what the piston manufacturer's specification is, as the piston expansion rate might be different to OEM.

Bob

jjrider 26 Sep 2014 18:28

This is the civilized forum !:innocent: We're not from Aussie :whistling:



censorship !

THUMPTHUMPTHUMP 26 Sep 2014 20:19

A forged piston has a larger piston to cylinder gap. I believe wisco requires .004 in. THUMPTHUMP

Zergman 27 Sep 2014 13:04

Oh yes, I'm blind...

I was too busy playing with the box contents and searching the instructions for the clearance. But the clearance is on the package: 0,003 in or 0,076mm. doh

Zergman 10 Nov 2014 07:41

Does anyone know where I could buy a lower cam sprocket (the small one, on the crankshaft)?
Seems like there's a lot of top sprockets, which bolt on the cam itself, but I can't find lower ones...

xtrock 10 Nov 2014 07:46

Quote:

Originally Posted by Zergman (Post 485424)
Does anyone know where I could buy a lower cam sprocket (the small one, on the crankshaft)?
Seems like there's a lot of top sprockets, which bolt on the cam itself, but I can't find lower ones...

Buy from yamaha dealer.

Zergman 16 Dec 2014 07:38

Quote:

Originally Posted by xtrock (Post 485425)
Buy from yamaha dealer.

Ohhhh yeah. Yamaha dealer here quoted me around 640Euros for a crankshaft kit (which includes both timing sprockets, crankshaft, con rod).

I've got a connecting rod kit already, paid around 100Euros for it, and I'm not spending extra 540Euro on a single sprocket I need plus something I don't.

Once I take the engine apart I'll check the condition of the smaller sprocket, and I might replace only the bigger one... Or keep both used, as they look good anyway.

Mezo 16 Dec 2014 10:07

Partzilla/boats (same company) cheapest prices. :thumbup1:

Mezo.

steveloomis 16 Dec 2014 14:56

Second the Partzilla/Boats.net for parts. They have recently expanded their local storage and have more parts in stock. I used them all the time. Their on-line parts manual is good, if it shows up there, it is usually available from Yamaha.:clap:


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