adjustable pushrods

2

2wheelmadman

Member
I got the adjustable pushrods installed as per the pics and narrative on this forum (and other ones) the bike runs for 15 mins or so and then gets so hot it smokes, backfires, and spits finally dying out. WTF. I used the adapter and balloon method to find tdcc, did 24 flats for the rod extension and it runs like shit, I even reset the Super G carb to S & S specs. What is causing the motor to get so hot so quickly, it used to run fine, obviously Im doing something wrong? any tips, tricks?
 
Mickmorris

Mickmorris

Well Known Member
Supporting Member
2wheelmadman said:
I got the adjustable pushrods installed as per the pics and narrative on this forum (and other ones) the bike runs for 15 mins or so and then gets so hot it smokes, backfires, and spits finally dying out. WTF. I used the adapter and balloon method to find tdcc, did 24 flats for the rod extension and it runs like shit, I even reset the Super G carb to S & S specs. What is causing the motor to get so hot so quickly, it used to run fine, obviously Im doing something wrong? any tips, tricks?
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I’m not sure what the adapter & balloon methods are for verifying TDC but I always use the flywheel myself. This is indicated by a T:F in the inspection hole for the front cylinder on the compression stroke and a vertical line in the hole for TDC on the rear compression stroke. The piston will be at the top twice in a 4 stroke engine cycle. Maybe it was on the exhaust stroke. You should redo your adjustments and make sure the lifters are pumped up when you do it. You will feel air at the plug opening on both the compression and exhaust stroke. However the compression stroke is much more powerful. Once you confirm your at TDC on the compression stroke let the lifters bleed down for 20/30 minutes before adjusting.
 
2

2wheelmadman

Member
Tx for your advice.
Another question or two.
1. How long should a cylinder hold compression for? 2 mins? 5 mins? Or?
2. Should the piston at tdc be right at the top of the cylinder or should it be down from the top in the cylinder 3-4"?
 
Mickmorris

Mickmorris

Well Known Member
Supporting Member
2wheelmadman said:
I forgot to add, i have 210 psi in the front cylinder and 208 psi in the rear cylinder, i believe that's ok.
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Wow. That seems pretty high. I would think it would be around 180/190 psi. Anything over 200 is like racing application. 10:1 or more I’m thinking. John Sachs would know more about that than anyone. I’m not sure how long typically the cylinders would hold that under testing conditions. But you can get a TDC tool from S&S for verifying the exact location of TDC through the spark plug opening. Just have to be real careful not to damage the top of the piston. I have one & rarely use it. Just easier to use the flywheel. The piston should only be a inch or so below the bottom of the spark plug opening. You can see this on the pic of the tool. IMG_0335.jpeg
 
Mickmorris

Mickmorris

Well Known Member
Supporting Member
2wheelmadman said:
I'm thinking the pushrods are installed correctly but the excessive overheating in 10 mins or so is indicating a failing/failed oil pump. Any thoughts on this?
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There is that possibility. They do go bad occasionally. Something is certainly amiss for it to get hot that quickly. Did you happen to check the engine temperature with a digital thermometer?
 
HMAN

HMAN

I just like my Freedom
Supporting Member
Best thing you can do is revisit the LAST thing you did. If it ran fine before changing the pushrods, logic says you fkd up somehow. Pull it apart again and look close. Is it possible you mixed up the intake/exhaust? One rod WILL be shorter than the other to begin with. Just my thoughts. But I aint that bright.....
 
2

2wheelmadman

Member
Not yet but I will. It gets so hot it starts back firing and finally quits. It shouldn't get that hot in 60+ degree weather, odd thing is my oil temperature gauge on the oil tank never goes above 160 or so, that leads me to believe it's not circulating the oil.
 
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