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Which Compression Tester?

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normally compression comes right back up around 150 with a wet test .unless its a valve issue

Or something more piston/cylinder catastrophic, like, say, a cracked piston?

Go ahead, ask Vacman how he knows...

Not sure if oil could have filled the chasm in the cracked piston well enough to seal it up. Maybe if you filled the cylinder half full and did the test quickly enough. lol

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reminds me of what i found when I first got my bike and it wasnt running right/ showing low comp. My jug was totally fine though somehow. Good luck Tim get her done!

PHOTO_20130527_074318_zpse9feddfc.jpg

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Not sure if oil could have filled the chasm in the cracked piston well enough to seal it up. Maybe if you filled the cylinder half full and did the test quickly enough. lol

If one had enough oil and could move VERY quickly. Maybe 90w gear oil. Or maple syrup.

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reminds me of what i found when I first got my bike and it wasnt running right/ showing low comp. My jug was totally fine though somehow. Good luck Tim get her done!

PHOTO_20130527_074318_zpse9feddfc.jpg

Merdé.

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Back on topic...

Kato - OUCH! that does not look good. Glad to hear your cylinder was still good - rotax baby!

350thumper - thanks for the tip on the wet test. I assume you've done it a few times? It might be worth testing.

In theory, what might cause a ring to crack? (not saying that is even my issue - I ask so that I may learn mo info!).

Piston slap is caused by excess wear on the piston due to friction and heat? High mileage or high revved motors may cause wear/deformation of the piston?

I pray my cylinder is still not scored and is still truly round but we'll find out soon.

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Ya your gonna have to mic the bittom of your cyclinder any how once its disasembled sometimes the bottom of the jug can be severly worn which causes blow by when piston is down . Even though clearance is good near the top.

Once the head is off you can place solvent or something non flammable.. into the intake port and wait for it to seep through the valve area. For the exhaust valve do the same ... spray the carb cleaner or whatever yur using into the exhaust port ... the valve shud hold the liquid back.

If not theres a great machine shop on el cajon blvd..
The guy does great work at a very fair price.

The reason you want to do as many test as possible is because you do not want to miss anything. Once you have the engine taken apart you won't be able to do the tests. It's worth taking five extra minutes on a test so you can be absolutely positive that you were repairing the right thing that way when you compose your parts list you can do it effectively by ordering the right part and keeping the cost down and possibly saving more trips back to the dealer or worse yet ordering the wrong stuff online than rebuilding the whole engine and finding out you still have a problem that would totally suck .

I may know a few things about motorcycle repair only because I do it for a ( curse) living...
But the collective conscious of SDAR has more knowledge than I ever will. Your doing the right thing by asking the entire forum. Vacman sounds like he has a good bead on your situation. And all the others even if they/we may be joking around a lil bit sometimes ..

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I may just be a beer drinking wrench turner working from a dirty crowded garage, but when I feel air coming out of the inspection hole on the crankcase during the leak down test, I'm pretty sure it's not escaping past the valves. :smile_anim:

Now comes the decision of whether to do just the top end, or crack into the case and do some crank work, wide ratio gears, etc. The head should be gone through no matter what, only makes sense when we have it apart.

When is the tear down party, Tim?

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And thus the snowball begins it's descent down the hill.

"Once you're in there, you might as well..."
"If I do that, I should do xyz to really make it right"

"No use just doing xyc without abc"

"While I'm in there, I might def"

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And thus the snowball begins it's descent down the hill.

"Once you're in there, you might as well..."

"If I do that, I should do xyz to really make it right"

"No use just doing xyc without abc"

"While I'm in there, I might def"

You should see the parts list when it's all totaled up. Yikes. Could have (should have?) just bought a plated, low hours 2009 300xc-w for less money!

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And thus the snowball begins it's descent down the hill.

"Once you're in there, you might as well..."

"If I do that, I should do xyz to really make it right"

"No use just doing xyc without abc"

"While I'm in there, I might def"

You should see the parts list when it's all totaled up. Yikes. Could have (should have?) just bought a plated, low hours 2009 300xc-w for less money!

I doubt he could by the KTM as cheap as rebuilding(upgrading his motor). I guess if you buy the KTM you can have this discussion all the time. :lmaosmiley:

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And thus the snowball begins it's descent down the hill.

"Once you're in there, you might as well..."

"If I do that, I should do xyz to really make it right"

"No use just doing xyc without abc"

"While I'm in there, I might def"

You should see the parts list when it's all totaled up. Yikes. Could have (should have?) just bought a plated, low hours 2009 300xc-w for less money!

I doubt he could by the KTM as cheap as rebuilding(upgrading his motor). I guess if you buy the KTM you can have this discussion all the time. :lmaosmiley:

I was referring to the "assembly of parts" that I bought from Bowers and my resulting expenses in restoring it to glory. Tim's repair should be an order of magnitude less expensive. I hope. :)

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And thus the snowball begins it's descent down the hill.

"Once you're in there, you might as well..."

"If I do that, I should do xyz to really make it right"

"No use just doing xyc without abc"

"While I'm in there, I might def"

You should see the parts list when it's all totaled up. Yikes. Could have (should have?) just bought a plated, low hours 2009 300xc-w for less money!

I doubt he could by the KTM as cheap as rebuilding(upgrading his motor). I guess if you buy the KTM you can have this discussion all the time. :lmaosmiley:

OK hammer.

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And thus the snowball begins it's descent down the hill.

The question is how far down the hill before you cannot return....

Having never had a bike's motor fail, I'm already preparing for the worst. I'm collecting aluminum cans in my neighborhood. I have a few large candles lit in my dark living room and am playing this on repeat..

On a more serious note, I'm still a little bummed and miffed about the bike failing since I rode it to camp. Had there not been support vehicles to haul my bike through the remainding days, I would probably still be living in the desert at Coco's Corner.

New kibblewhite SS valves/springs? New JE piston/rings? Re-nikasil stock cylinder or big bore? Wide ratio gear set requiring complete case splitting? Roll it off the OB Pier?

I actually might bring some cake to the Teardown Party.

Big Note: I very much appreciate the good info shared on this thread - Thank You! I'll keep this thread updated with pics, info and additional questions ha!

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Time for this...

IMAG0486.jpg

IMAG0513.jpg

I'll look to see what I paid for my Eddie Sisneros rebuild..

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Teardown Party this weekend!

I did some preliminary pricing on things just to get a better understanding of what I might be getting into and how far down the slippery slope I may end up:

(Wide Ratio gears would be pretty far down the slipper slope. Here is a thread about them on the DRZ http://dualsport-sd.com/forums/index.php?/topic/15433-drz400-wide-ratio-transmission-gears/ )

If the cylinder is not scored and can be reused:

--JE std bore (90mm) 12.1 piston kit is $167

--Wiesco std bore (90mm) 12.2:1 piston kit is $145

--Tusk Top end gasket kit $23

post-14322-0-27347100-1413052718.jpg

--OEM Suzuki Cam Chain $70

--Hot Cams Cam Chain $48

post-14322-0-72795500-1413052792.jpg

If the stock cylinder needs cleaning/light hone:

--Flex-Hone Cylinder Ball-Hone 90-95mm $52

post-14322-0-64903900-1413052825.jpg

--Flex-Hone Cylinder Wash Brush $14

post-14322-0-67310200-1413052830.jpg

--Flex Hone Oil 8oz $9

post-14322-0-29592100-1413052835.jpg

If the cylinder is scored and must be replaced/replated:

--JE oversize (94mm) 12.1 piston kit $160-192

--big bore gasket kit $60-75

post-14322-0-87367900-1413052864.jpg

--Big Bore Kit 434cc namura? cylinder with JE oversize (94mm) 12.1 piston $400

--Big Bore Kit 434cc Cylinder Works cylinder and probably a Vertex (94mm) piston $435

post-14322-0-35515000-1413052882.jpg

If headwork is needed:

--Kibblewhite Black Diamond Intake Valves $27 x 2 = $54

post-14322-0-75311800-1413052917.jpg

--Kibblewhite Black Diamond Exhaust Valves $27 x 2 = $54

post-14322-0-51027100-1413052935.jpg

--Kibblewhite Valve Spring Kit $110

post-14322-0-94356100-1413052947.jpg

--Tusk Valve Spring Compressor $40

post-14322-0-76015700-1413052961.jpg

If the case needs to be split:

--ACT Wide Ratio Gears $620

post-14322-0-04682800-1413053387.jpg

--Motion Pro Flywheel Puller 38mm $42

post-14322-0-40013700-1413053418.jpg

--Tusk Engine Lock Up Tool $8

post-14322-0-96204400-1413053424.jpg

--Tusk Crank Bearing Ring + Gear Puller Set $60

post-14322-0-26129000-1413053462.jpg

--Tusk Bearing Remover $95

post-14322-0-07656300-1413053482.jpg

--Tusk Crankcase Splitter/Separator $70

post-14322-0-01731800-1413053526.jpg

--Tusk Crankcase Puller/Installer Tool $70

post-14322-0-07442000-1413053567.jpg

--Complete gasket kit $101

post-14322-0-72684600-1413053602.jpg

--Bottom End Bearings - I haven't parts fiched them but ~$300?

post-14322-0-97723400-1413053620.jpg

--Misc sealant, anti-seize, assembly lube, oil, threadlocker, rtv gasket $100

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I didnt see the valve guides on there.

Theres a few ways to shave off some cost.

Like renting the honing brush from oriley loaner tool program.

As far as honing I use brake cleaner as a lucricant. I know it sounds wierd but once you do it you wont ever do it with oil again because it stays clean( not recommended for the total rookie) If theres honing brush grit left inside the cyl it will wear out your new piston.

Also you may want to let the local head shop purchase your seals and guides and valves. They make one or two dollars if that, but shud there be ap prob m they will take full responsibilty plus it keeps your running around to a minimum just drop off and pick up from your head shop.plus its always a good idea to support your local repair shop.

Im thinking your gonna try to keeps costs down so you can pay for the beer (labor).

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Spend money on a cometic gasket set. The tusk gaskets are junk.

Based on what you and I have discussed for your future plans, I would only do the minimum to make your drz run again. The sad truth is you'll never get back even 25% of your investment from fixing it.

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Spend money on a cometic gasket set. The tusk gaskets are junk.

Based on what you and I have discussed for your future plans, I would only do the minimum to make your drz run again. The sad truth is you'll never get back even 25% of your investment from fixing it.

I second that Tusk gaskets are junk. Learned that the hard way...

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I have thd tusk case tools and a valve spring tool if u need to borrow. If I had less going on I would offer to help with the work. You can use a scotchbright pad on the cylinder also, hone is probably not necessary. I have a bore gauge also. Hit me up for tools...

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