- Joined
- Jan 1, 2005
- Messages
- 187
Hello fellow riders. It's been a while since my last post( March 2005). I used to be a regular on INOLIST until it got messed up to the point I couldn't use it so now I'm back here on the urging of my friend "milfordite".
So here is my latest tale of woe.
THE FALL AND RISE OF ‘Pa’ MY TRUSTY NORTON
Late in June of 2014 I was riding one of my favorite rural routes through Northern Kentucky taking the back way to a nice little restaurant in Cynthiana. ‘Pa’ slowed down once on his own then sped back up I tried to fathom what that could be and continued motoring on. Then through a fast tight sweeper my MKIII refused to respond to the throttle making it a little difficult to hold my line then came back to life. A few more miles of twisting roads over ridges and through the valleys and all seemed well. A mile after pulling onto the highway towards Falmouth ‘Pa’ Seemed to choke up so I pulled in the clutch to rev it up and clear his throat and the most horrible noise came from under the tank and the motor stalled . I was fortunate that at this very moment there was a safe place to pull off the side of the road and get out of danger. It didn’t hurt that there was a large shade tree to rest under and that we were on the top of a high ridge with cell service.
A quick visual check of the engine and my heart went into my throat. This was the closest I had ever been to crying over a broken machine. My little one way check valve in my oil supply line had become a no-way check valve starving the engine of lubricant and locking it up.
Norton owners have been dealing with wet sumping for a long time with lots of different theories for cause and correction. Horror stories have been told and repeated about check valves and I am here today to repeat what was told to me many times by people smarter than I. “If you have one of those little check valves that are silver on one end and black on the other with a clear window in the middle run, don’t walk to your Norton and remove that valve before starting the engine even one more time!”
Here is how big a disbeliever I was; Two years after installing my first valve I discovered it had “come apart” while doing a routine pre-flight inspection. I got another one under warranty from my supplier and replaced it. Two years after that episode I was stranded on the side of the road in rural Ky. on a broken motorcycle with a separated check valve just like the first one.
I had ‘Pa’ hauled back to town and stored in my son’s garage downtown. My dilemma now was that I had torn down the dilapidated shed I called a garage and was in the process of building a proper workshop for my motorcycles. (No cars allowed!) I had no place to work on the Norton and he sat forlornly in limbo for six months until the new garage was finished and all my tools and equipment could be moved in.
The initial diagnosis after disassembly; drive side connecting rod broken, crankshaft journals looking frightful, pistons and cylinder scored and scorched, and a contusion to the case behind the drive side journal where the rod tried to escape.
The crankshaft only needed -.020 removed to be serviceable again. A wonderful friend (milfordite)donated a good used rod along with a lot of priceless technical information and moral support. The cylinders went +.040 having been +20 earlier in life. I went through the head and after a regrind on the valves and new stem seals all was good there. While I was there I replaced the cam chain and the primary chain and went through chain tensioners in the MKIII drive side. The crank was rebalanced along with the rods and pistons.
Upon recommendation from people who know way more than me I changed the front sprocket to 21 teeth op from 20 and installed a new camshaft with a “street/touring grind”. I also modified the sprockets and installed the 520 “O” ring chain. The rear Isolastics was completely worn out so new front and rears were installed. I also had my plain clutch plates machined flat by a precision grinding company after noticing unusual wear patterns.
Having been a mechanic for over forty years I did all of the work except the machining myself with a little help from friends and family.
My financial adviser (wife) told me the day I brought the broken Norton home that I was to fix it, regardless of the cost. She said the Norton was too important to me to just let it sit. This was after spending a small fortune on my new workshop that was also her Idea.
Three months and two-thousand dollars later I have a machine that is by far better than I had before. The different sprocket and cam made a world of difference, along with the new Isolastics the bike cruises with less effort and less vibration at 70 mph then I ever would have thought possible. The 70 to 90 mph time is reduced to just a quick twist of the throttle. The overall power band and response to the throttle is unbelievable and yet it is still the same docile machine in town and traffic.
After eight hundred miles and three oil changes, four head re-torques, and four valve adjustments ‘Pa’ starts first kick, idles smooth, runs like a scared cat and holds the place of honor in the new shop. He really seems to like the flogging he is getting as we break in the engine and relearn our blend of new and old personalities.
Ride On (Nortons of course)
Dave
©The Buckeye Rider
Cincinnati, Ohio
5/21/2015
So here is my latest tale of woe.
THE FALL AND RISE OF ‘Pa’ MY TRUSTY NORTON
Late in June of 2014 I was riding one of my favorite rural routes through Northern Kentucky taking the back way to a nice little restaurant in Cynthiana. ‘Pa’ slowed down once on his own then sped back up I tried to fathom what that could be and continued motoring on. Then through a fast tight sweeper my MKIII refused to respond to the throttle making it a little difficult to hold my line then came back to life. A few more miles of twisting roads over ridges and through the valleys and all seemed well. A mile after pulling onto the highway towards Falmouth ‘Pa’ Seemed to choke up so I pulled in the clutch to rev it up and clear his throat and the most horrible noise came from under the tank and the motor stalled . I was fortunate that at this very moment there was a safe place to pull off the side of the road and get out of danger. It didn’t hurt that there was a large shade tree to rest under and that we were on the top of a high ridge with cell service.
A quick visual check of the engine and my heart went into my throat. This was the closest I had ever been to crying over a broken machine. My little one way check valve in my oil supply line had become a no-way check valve starving the engine of lubricant and locking it up.
Norton owners have been dealing with wet sumping for a long time with lots of different theories for cause and correction. Horror stories have been told and repeated about check valves and I am here today to repeat what was told to me many times by people smarter than I. “If you have one of those little check valves that are silver on one end and black on the other with a clear window in the middle run, don’t walk to your Norton and remove that valve before starting the engine even one more time!”
Here is how big a disbeliever I was; Two years after installing my first valve I discovered it had “come apart” while doing a routine pre-flight inspection. I got another one under warranty from my supplier and replaced it. Two years after that episode I was stranded on the side of the road in rural Ky. on a broken motorcycle with a separated check valve just like the first one.
I had ‘Pa’ hauled back to town and stored in my son’s garage downtown. My dilemma now was that I had torn down the dilapidated shed I called a garage and was in the process of building a proper workshop for my motorcycles. (No cars allowed!) I had no place to work on the Norton and he sat forlornly in limbo for six months until the new garage was finished and all my tools and equipment could be moved in.
The initial diagnosis after disassembly; drive side connecting rod broken, crankshaft journals looking frightful, pistons and cylinder scored and scorched, and a contusion to the case behind the drive side journal where the rod tried to escape.
The crankshaft only needed -.020 removed to be serviceable again. A wonderful friend (milfordite)donated a good used rod along with a lot of priceless technical information and moral support. The cylinders went +.040 having been +20 earlier in life. I went through the head and after a regrind on the valves and new stem seals all was good there. While I was there I replaced the cam chain and the primary chain and went through chain tensioners in the MKIII drive side. The crank was rebalanced along with the rods and pistons.
Upon recommendation from people who know way more than me I changed the front sprocket to 21 teeth op from 20 and installed a new camshaft with a “street/touring grind”. I also modified the sprockets and installed the 520 “O” ring chain. The rear Isolastics was completely worn out so new front and rears were installed. I also had my plain clutch plates machined flat by a precision grinding company after noticing unusual wear patterns.
Having been a mechanic for over forty years I did all of the work except the machining myself with a little help from friends and family.
My financial adviser (wife) told me the day I brought the broken Norton home that I was to fix it, regardless of the cost. She said the Norton was too important to me to just let it sit. This was after spending a small fortune on my new workshop that was also her Idea.
Three months and two-thousand dollars later I have a machine that is by far better than I had before. The different sprocket and cam made a world of difference, along with the new Isolastics the bike cruises with less effort and less vibration at 70 mph then I ever would have thought possible. The 70 to 90 mph time is reduced to just a quick twist of the throttle. The overall power band and response to the throttle is unbelievable and yet it is still the same docile machine in town and traffic.
After eight hundred miles and three oil changes, four head re-torques, and four valve adjustments ‘Pa’ starts first kick, idles smooth, runs like a scared cat and holds the place of honor in the new shop. He really seems to like the flogging he is getting as we break in the engine and relearn our blend of new and old personalities.
Ride On (Nortons of course)
Dave
©The Buckeye Rider
Cincinnati, Ohio
5/21/2015
