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Cylinder, Piston rings - replacement problem

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Hi, 

So, i decided to replace DRZ400 E 2002 piston rings. Ordered OEM rings, and head gaskets.

1) Following Clymer step by step guide replaced rings:

    a] Honed cylinder

    b] Rotated rings according requirements. 

And put up everything back. Piston and rings were not greased with oil (they were inserted dry). Other parts were lubed.

2) Engine break in - I used mineral motorcycle oil "MOTUL 3000 PLUS 4T 10W40 MINERAL OIL". Thinking I will do 20 miles hard break-in and change filer & oils and do another 20-50 miles before moving to regular oild.

 

Problem:

1) So I started my DRZ, warmed it up for around 5 minutes in mean time adjusted MCCT.

2) I have ridden not more than 0.3 miles in 1st, 2nd gears (various throttle positions) before I started hearing hard & loud tickling noise in upper head. So I have driven it back home.

3) I suspected that this noise comes from Cams Autodecompression - So I read the forums and removed autodecompression part.

4) Put everything back again, start engine and I still hear this loud tickling. 

5) Removed head, cylinder and I see two scratches in cylinder surface. I can feel the scratch with finger nail. 

 

Question:

What could have been the cause of these scratches? What did I missed? Whats the best option to proceed?

 

 

 

 

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3 hours ago, 38super said:

What was there ring gap before installing on piston?

So the case for problem is closed. After half day brake, got back to investigate the possible cause, and I saw the piston pin close to piston edge and right side piston pin circlip was missing.. (yes I reused old ones :( ). Hard lesson learned.

 

What options do I have now?

a] Is cylinder head usable/fixable? Piston & new rings seem to be fine.

b] New Athena big bore kit costs less that new cylinder.

 

I also need to find missing circlip which is missing now :(

20170525_222839.jpg

Edited by Albertas As
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12 hours ago, Albertas As said:

Hi, 

So, i decided to replace DRZ400 E 2002 piston rings. Ordered OEM rings, and head gaskets.

1) Following Clymer step by step guide replaced rings:

    a] Honed cylinder

   What did I missed? Whats the best option to proceed?

No kidding? The Clymer said to use a ball hone on a nic-a-sil bore? :naughty:

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18 hours ago, ohiodrz400sm said:


The standard bore kit can be found for around 400. The cylinder only can be had for around 240. Dirt cheap is a relative term. Compared to an Athen kit it's cheap.

Understood. Wanted to make sure I wasn't missing a sweet deal somewhere.

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If you just buy a cylinder and use your old piston (with new rings I hope ??) , you'll need to accurately measure the bore to make sure you have the correct clearance for the piston . I don't know how much the various brands vary in size and if they truely measure pistons to match for each cylinder or if they are simply finished at one size +/- a certain spec and then just grab pistons from a pile hoping they'll all be within spec .This is probably how is done but I haven't had a big sampling # to know for sure .  Vertex you can get 89.94mm, 89.96mm ,89.97mm ,89.98mm ect... to get a precise clearance to whatever the cylinder actually is .

Edited by jjktmrider
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