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Need Flywheel help.

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So i'm reviving the drz from about 2 years of neglect. To keep this as short as possible... Built motor, big bore, stroker crank, rhc cams, mrd ssw. I've got a second bad head gasket. This is the second headgasket to go, I think i'll run the stock 3 ply base gasket this time for the lower compression. When i was pulling my head off i noticed the cam lobes were never at 10/2 at TDC, i checked intake and exhaust stroke as well. I pulled everything off, head, jug, and now i can see the crank and the piston. The TDC mark on the flywheel, when visible through the port window is just when the piston is coming past DEAD CENTER (the piston at the bottom of it's stroke) and no where near where i believe it should be (the piston furthest away from the crank. I hope i'm not upsetting anyone posing this question here, i've scoured the interwebs to no avail!

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Pull the flywheel and check for a sheared flywheel key.  Obviously the Top Dead Center (TDC) mark on the flywheel needs to be when the piston is actually at the top of the stroke.  If the key is not sheared and for some strange reason the flywheel is marked incorrectly, you will have to create your own TDC mark.  Use a piston stop and degree wheel to find true TDC.  The flywheel needs to be clocked to the crank correctly also for ignition timing.

 

For the sake of conciseness, the opposite of TDC is Bottom Dead Center (BDC).  Simply dead center has no meaning as far as I know.

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Thanks Noble, My stator did eat my one way bearing bolts inside my flywheel. I have since cleaned that up and changed the stator. I remember putting it back on and the key was in tact. I'll pull the flywheel cover off today and report my findings. 

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So i'm reviving the drz from about 2 years of neglect. To keep this as short as possible... Built motor, big bore, stroker crank, rhc cams, mrd ssw. I've got a second bad head gasket. This is the second headgasket to go, I think i'll run the stock 3 ply base gasket this time for the lower compression. When i was pulling my head off i noticed the cam lobes were never at 10/2 at TDC, i checked intake and exhaust stroke as well. I pulled everything off, head, jug, and now i can see the crank and the piston. The TDC mark on the flywheel, when visible through the port window is just when the piston is coming past DEAD CENTER (the piston at the bottom of it's stroke) and no where near where i believe it should be (the piston furthest away from the crank. I hope i'm not upsetting anyone posing this question here, i've scoured the interwebs to no avail!

From what you posted

It appears you were checking on on the wrong crank stroke.

The picture with the cams is exactly what I would expect to see with the timing mark in the window and the crank on a wrong crank stroke.

The bike would not run at all if it was off timing as much as you think it is.

Three layer base gasket might help with the head gasket issue but really you need cams with more overlap designed for a stroker.

Might also use the suggested head bolt tq of 43 ftlb and copper coat the head gasket. Make sure the head and cylinder are very clean before assembly

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From what you posted

It appears you were checking on on the wrong crank stroke.

The picture with the cams is exactly what I would expect to see with the timing mark in the window and the crank on a wrong crank stroke.

The bike would not run at all if it was off timing as much as you think it is.

Three layer base gasket might help with the head gasket issue but really you need cams with more overlap designed for a stroker.

Might also use the suggested head bolt tq of 43 ftlb and copper coat the head gasket. Make sure the head and cylinder are very clean before assembly

Welllllll look what i found

IMG_7494.jpg

IMG_7495.JPG

IMG_7496.jpg

IMG_7497.jpg

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So  the question now is why it sheared? Is that a stock flywheel?

 

Verify it locks tight on the taper by assembling and tightening the flywheel without the key.  Then repeat with the key. In some instances the key is too tall due to the keyway in the crank or the flywheel being shallow.

 

It almost had to be the key with the piston down and the Flywheel TDC mark in the window. 

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So  the question now is why it sheared? Is that a stock flywheel?

 

Verify it locks tight on the taper by assembling and tightening the flywheel without the key.  Then repeat with the key. In some instances the key is too tall due to the keyway in the crank or the flywheel being shallow.

 

It almost had to be the key with the piston down and the Flywheel TDC mark in the window. 

Yes i think you're spot on with this being the culprit. This motor is really hard to turn over with the stock starter. I had a larger lead acid battery and now a lithium polymer. I ended up pull starting the bike the last time it ran, i wonder if that combined with the bolt not being torqued to spec would be the source of the shear. It ran decent and then felt like it was losing power rapidly and then died. I will go through the process of instaling the flywheel without the new woodruf key and then with. 

From what you posted

It appears you were checking on on the wrong crank stroke.

The picture with the cams is exactly what I would expect to see with the timing mark in the window and the crank on a wrong crank stroke.

The bike would not run at all if it was off timing as much as you think it is.

Three layer base gasket might help with the head gasket issue but really you need cams with more overlap designed for a stroker.

Might also use the suggested head bolt tq of 43 ftlb and copper coat the head gasket. Make sure the head and cylinder are very clean before assembly

Are the Rhc cams that eddie does not still the bees knees for the stroker motor? I thought they were a few years back. 

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Yes i think you're spot on with this being the culprit. This motor is really hard to turn over with the stock starter. I had a larger lead acid battery and now a lithium polymer. I ended up pull starting the bike the last time it ran, i wonder if that combined with the bolt not being torqued to spec would be the source of the shear. It ran decent and then felt like it was losing power rapidly and then died. I will go through the process of instaling the flywheel without the new woodruf key and then with. 

Are the Rhc cams that eddie does not still the bees knees for the stroker motor? I thought they were a few years back. 

 Are they RHC 187 cams? If so then yes, that was/is a good choice for the stroker.

 

The key is really only an indexing piece.. Not designed to stop rotation on the crank.. That is what the taper is for.

 

If the flywheel was not installed correctly, and not seated on the taper,, and or allowed to work loose because of a loose bolt.. then yes the woodruf key can shear. 

 

I have one DRZ motor I repaird running around for the last few years with NO crank key at all. The flywheel was indexed with a timing wheel and dial indicator  

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OK, so i've got it all back together and went to fire it up. First off i fried my shorai lithium battery. So i've got a ballistic 12 cell here now. This is the battery i've been needing the whole time! The bike is studdering a bit and thinking about starting BUT no joy. My carb bowl was filthy filthy, i've cleaned it all up and cleaned the jets as best as i can. I'm thinking they are the culprit now. Any of your guru's have any jetting advice for me?

 

Here's where i stand now. 48 pilot, 80 pilot air, and 179 main. 

+4mm stroker

Big bore kit

fcr41

rhc cams w/ eddies headwork

mrdssw pipe

 

Also i have a r&d adjustable accelerator pump and i've pushed out the ball and spring from the port leading into the pump. For some reason i have a set screw pushed into that hole. in the directions it calls for the plug in the hole next to it which on my carb is already plugged. Anyone have any ideas? God i'd sure love to get this thing up and running!

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