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About fyusmal

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  1. Tore into the engine and everything seems to be in place. Next possible suspect: The 3rd piston ring (oil ring, fits on the 3rd groove counting from the top of the piston) may not be original Wiseco. What I have on is a 3 piece oil ring, 2 thin rings and a wavy ring that fits in between. Is this the correct assembly? Does anybody have a picture of wiseco rings?
  2. Put everything back together with proper shims in place and the knocking sound is still there. Looks like its time for bottom-end exploratory surgery. Will keep you guys posted.
  3. OK Eddie, guys.. I have re-opened the top end again, and this time with my own hands as I have lost faith with the mechs here. Results: 1. Shims were double stacked on 3 of the valves, 2 outlet, one inlet, by the mech who did the top end in order to gain the right clearnce. 2. Bore tolernce OK. Within factory diameter range. 3. New piston / gudgeon pin OK. Within factory diameter range. No physical damage on top indicating valve tapping. Skirting OK. Usual carbon deposit build up. 4. Cam timing OK. As specified in service manual. (Thanks Eddie, was the first thing i checked) 5. New rings OK. Within range. 6. Gasket sealing liquid was used on base and block gaskets even tho gaskets were definitely new. 7. Con-rod side to side play within sevice limits (Thanks again Eddie, u were right on this) 8. Auto de-comp mechanism on outlet cam OK. Spring return works fine. So it seems the stacked shims is the culprit? Knocking from movement of the 2 shims stacked on each valve amplified by the engine during valve return lift? Is there anything else I should check while the top end is open?
  4. I was given another possible scenario by another mech: The compression on the new rings and high comp pistons are much higher than before, with the worn out rings burning oil, such that it revealed a worn out crankshaft bearing from the stroke cycles. Hence resulting in knocking noises. What do you guys think of this explanation?
  5. how did the oe piston look? any signs of piston slap? skirt bottom polished? -oe piston had very minor polishing on the skirt bottom. about 0.5mm height along skirt. hows oil consumption now? its seems to have stopped consuming oil at silly rates. If any its coming from the leak on the base / mid gasket. does it knock all the time or only certain rpms? -all the time was cyclinder taper measured and in spec? -it was not measured but its a brand new wiseco forged
  6. Its one of the possibilities. I had 4 different opinions from 4 different mechs. Of wich these 3 made sense. 1. Incorrect valve clearance resulting in valve tapping against the high comp taper 2. Worn out conrod bearing resulting in hyperextension of piston when on upstrroke hence hitting the top 3. Highcomp piston not designed to be used with thinner e-model gaskets I cannot figure out what may be the problem but I am trying my best to not split the engine.
  7. Its got a MCCT and new cam chain fitted. Lightly loosening the MCCT to alter the timing did not seem to have any effect on the frequency of the knocking nor the loudness.
  8. I have a Y2K S model. Just completed a top end overhaul with new rings, high-comp wiseco (standard bore) piston and E model base gasket. Bike was fine before the overhaul except it was burning engine oil at an accelerated rate. Hone marks on the bore still visible when top end was out. Now there is a knocking sound similar to knocking the handle of a screwdriver against the block. It seems to be more pronounced from the right side of the engine than the left. Also engine oil is now leaking from base, mid and top gaskets. The base and mid gaskets are new. The mech has no idea what the issue could be without splitting the engine open. While the top was out, the conrod and crankshaft movements seemed normal. I use 98 octane fuel so its not pre-detonation issues. I use a MCCT and had a new cam chain fitted. I would be open to switching back to the original pistons if it would remove the knocking sound as I was after engine efficiency, not higher performance. This bike is used as a commute hence it has almost 90,000 Km on the clock. I'm stumped as to the source of the knocking. Any ideas guys?
  9. fyusmal

    Vacuum leak --> lean fuel mixture?

    Thanks Eddie. Lets say hypothetically that there is a vacuum leak somewhere along the line from the engine vacuum nipple. My bike runs an FCR-MX. The petcock and scott oiler both operates on vacuum from the engine vacuum nipple. With a leak, the bike will not run correctly but does this mean I am running a lean mixture in the combustion chamber and if undetected over a longer period of time may result in piston ring damage?
  10. Would a vacuum leak from the engine nipple vacuum line cause the air/fuel mixture to run lean? I have a scott oiler and the petcock vacuum running from the engine nipple vacuum line. My mechanic claims that any leak in this vacuum line will cause the bike to run lean and may result in piston ring seizure. Comments anyone?
  11. Y2k drz s in almost stock form except for Leo Vince pipes. 92,000Km on the odo. 1 valve service done at 85,000Km. Its been through floods, mud, silly climbs, rainforest trails, daily commuting with and without passenger, jumps, etc. Still goes like a champ. Just an oil change every 4000Km and oil filter change every alternate oil change. This bike is a tank in its own right.
  12. fyusmal

    DIY North Baja rides

    Thanks to everyone with the constructive comments and help. We were recepients of excellent hospitality by some good folks in San Diego who took us out to Baja. The ride could not have turned out any better. Now I am back in the office in Singapore wondering if it was all a dream. Fai
  13. fyusmal

    DIY North Baja rides

    Ok Guys I have no idea who this Mike Kay guy is and I do not ride Husky's in Singapore. And I have no idea as yet what truck my buddy in San Diego drives. In fact my ride is a DRZ400S and a GasGas EC200 smoker. And if the English seems too proper.. well its the national language here. Thanks for the advice. It seems the logistics of it all as a first timer could get quite maddenning. I am revisiting the option of a guided tour. Anyone riding Baja around 5th till 16th July? We would be happy to tag along if so. Fai
  14. fyusmal

    DIY North Baja rides

    I have seen numerous tours selling guided Baja rides but they cost quite a fair bit of dosh. Me and a buddy of mine have a truck and 2 bikes ready in San Diego. How feasable is it to do the ride unguided? We speak almost zero Spanish and have no idea where to start in planning the ride. Anyone with experience who can guide us along on this supposedly epic journey of sorts? GPS maps, places to stay, must see sights? fai