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[612cc]

So .. has anyone actually used the new sprag cage in the old housing ?

[Norm]

Thack I have a couple of Hondas and still ride my Interceptor which is pretty reliable

[Leon Novello]

I don`t think it`s good engineering practice to fit a sprag clutch to a single cylinder engine. So, what have we got today? Wrong-way brakes, stuck cylinder head, sprag clutch. This board makes me nervous even without Norm`s troubles.

[Norm]

Leon, my troubles are nearly behind me, I just have to pull the motor back out of the Meteor and fix the gearbox, fit the rechromed forks and it can get out of my hair, that only leaves the WDCO/Indian engined one to finish and that really only need the tank painted and I'm a free man to just go for a ride when I want, sorry just remembered I have this 36 Enfield motor sitting here that was rescued from a shed fire (some bits have melted off it, tappet door and part of the timing cover) that destroyed a friends shed where he lost everything, brand new Enfield with 400ks on the clock,Suzuki Boulevard about 3 years old, 1970 Bonneville,a very rare mint condition 400 Suzuki,and another bike I can't remember what it was, 3 cars and a brand new caravan. Luckily his 1938 fully restored Enfield was in the house so it was saved

[Top Draw]

Hi all I have replaced no less than three sprag clutches in 3 years 2 on my wife,s Bullet Electra and one for a fellow club member it is a very interesting problem but I have learned that there is a couple of ways you can prolong the life of these bearings.1 when engine is running and you want to switch off, use the decompressor lever rather than just turning off the key as this stops any risk of reverse rotation of the crank and allows the engine to come to a complete halt. 2. Make sure you have a good battery if the battery struggles to turn over the engine this is when you could have a potential damaging incident to the Sprag. 3 If the bike has not been started for a while gently turn engine over with decompressor engaged and ignition off this does allow some oil from the primary case to flick onto the starter drive coggs and hopefully the sprag bearing . also I only use the Electric start these days as it is stronger than my right leg and I know how it can go with the kick back which ultimately wrecks sprag clutches when a leg start is attempted and finaly if you do need to change the sprag replace the cog that it fits inside of aswell not just the bearing on its own as wear inside the assembly that cannot be seen can cause early failiure, learned this the hard way at £120.00 a pop alot of beer that wasnt drank for a while. ha ha best wishes too all

[Norm]

Top, only problem using the supposed decomp on an Electra is that it is actually a valve lifter which operates on the exharst tappet/cam folower. In their wisdom to fit this they downsized the tappet to a 6mm shaft diameter from a 9mm one on the Cast Irons and as a result Electras break the tappets, never heard of a Bullet breaking them. Means to replace the tappet you have to remove the cam spindle and the tappet guide and the barrel to fit a new tappet. Couple of tools in there to get this apart can be expensive for a once off job

[Thack]

Norm, that's fascinating and you're the first person to explain a weird breakdown to me.



With only a few hundred miles on the clock my Electra X cut out and ended up being taken back to the dealer on a truck. Turns out the head had snapped off the exhaust tappet. The dealer told me this was a one-off, never heard of it before, presumably a manufacturing fault. It was replaced and never failed again, but I was always suspicious and never entirely happy about why it failed.



Your explanation makes perfect sense - I had no idea they'd made the stem thinner. 9mm to 6mm is a big step, although presumably they must have done some kind of calculation that it would be OK.



Incidentally, the dealer made a bodge of the repair. On the journey home I was very concerned about the terrible noise from the valve gear, like one of the tappet gaps was way too high. And yet when I checked, the tappet clearances were perfect (push rod would just rotate, with no play, with the engine warm). To cut a long story short, I discovered that the exhaust tappet was not descending to the base circle of the camshaft, but hanging about 10 thou high.



Turns out they'd somehow installed the valve lifter too high (or something) such that it wouldn't let the tappet descend all the way down. I "cured" it by removing the circlip, which let the tappet work normally but obviously disabled the decompressor.



I didn't explore it any further as I got seven years of good service from that bike before trading it in. But I wonder - have you come across this before, where the valve lifter is installed too high and won't let the valve descend low enough?

[Norm]

Thack easy done if they don't get the tappet guide all the way in, hard to see in there if it is down properly. When I built my crossbred I used Bullet tappet guides and tappets and had to turn them down to suit the Electra cases which were probably 2mm smaller in diameter and had to have a step in them because the Electra bottom out lower that the Bullet, bit complex trying to explain

[612cc]

Hi Top
thank you for your very informative list of caring for the sprag , hope you don,t have to do any more sprag replacement s for a while yet ..
happy new year to you
cheers
kevin

[Norm]

Tops advice is good but you only have to stall it once at traffic lights and it can be all over, seen that done as well