it's not as if the OEM bmw valves have an untarnished reputation for reliability.
Swiss valves or not
- Thread starter redsoul
- Start date
richie moore
Registered user
I had the first of my valves in 1998 for racing, and I put them into a r100rt test engine that was used on the motorway 5 days a week, I inspect them every year, he has now covered 60000 miles on them, and they are still very good,they also stand 10000rpm in my race engines, and flow more air. they are one piece 214n stainless forgings with a plasma nitride coating and stellite inserted into the tip. they are also lighter than a standard valve. I will still fit bmw valves if people bring them to me but not swiss int I just dont want the comebacks.
So you are saying that you expect comebacks with the swiss valves and not the bmw valves.Is this because the bmw valves are tried and tested and will do 40,000 miles ish b4 major wear and tear and that the swiss valves are quite new in that the factory only opened for business in 1987 so dont really know alot about them......or have you had experience with these valves breaking
richie moore
Registered user
the racing sidecar engine had them in when he gave it to me, he had over revved it by his own admission but only to 9000 and the head came off one of the valves punched a hole through a piston, got cought on top of the conrod and came out through the top of the crankcase. jim cray can also tell a few stories thats why we dont use them.
ians
Registered user
While I fully appreciate Richies experience and expertise I would be interested to hear of any failures in road going bikes that rarely if ever hit the red line.
I woundn't put Castrol 20W50 in a race bike but it works fine in a road bike.
Just curious.
I woundn't put Castrol 20W50 in a race bike but it works fine in a road bike.
Just curious.
Richie are your valves available for general sale?
Thanks Richie......this is the kind of info i was looking for... an opinion backed up with hard evidence.
richie moore
Registered user
Yes my valves are for sale just look on my website. as for problems with swiss valves in road engines jim cray is your man but I do not think he will tell you about it, and it is not for me to say.
This thread might seem a bit like that Rob but was just trying to make an informed decision based on hard evidence rather than just heresay.The current wisdom
The current wisdom on valves is that Swiss Intervalves are the best available at the moment for road engines, the OEM valves are made in the States and the last batch supplied did not have the stellite tops to stop them wearing where they come in contact with the rockers, the manufacturers could not confirm whether they were going to make any more with hardened tops, without the stellite tops they are fine for water cooled engines, but not for air cooled.
A cautionary note on Intervalves.............there are some that have not had the ground finish on the stems, these have lathe tool marks going round the stem instead of the matt finish when ground, the unground ones tend to wear the valve guides prematurely, (under 10,000 miles) and so should be checked before fitting, if they unground they need to be changed.
There are also some one piece valves available, fine for race engines that are unlikely to do more than 1000 miles between rebuilds, good tough valves but the machining for the collets prevents the valves rotating in the collets and keeping the seats clean.
The current wisdom on valves is that Swiss Intervalves are the best available at the moment for road engines, the OEM valves are made in the States and the last batch supplied did not have the stellite tops to stop them wearing where they come in contact with the rockers, the manufacturers could not confirm whether they were going to make any more with hardened tops, without the stellite tops they are fine for water cooled engines, but not for air cooled.
A cautionary note on Intervalves.............there are some that have not had the ground finish on the stems, these have lathe tool marks going round the stem instead of the matt finish when ground, the unground ones tend to wear the valve guides prematurely, (under 10,000 miles) and so should be checked before fitting, if they unground they need to be changed.
There are also some one piece valves available, fine for race engines that are unlikely to do more than 1000 miles between rebuilds, good tough valves but the machining for the collets prevents the valves rotating in the collets and keeping the seats clean.
ians
Registered user
Thats interesting, but where did this information come from.
I am not doubting you, it's just it's quite explicit information that is hard to come by unless you are in the trade.
richie moore
Registered user
the information about the collets gripping the valve is true, having the valve float is regarded as bad practice,and as to wether it keeps the seats clean or not, I just cant tell any diffrence between one that floats and one that dosent. and I see about 10 heads a week, and have done for years, from some of the leading tuners. you will be hard pushed to find a leading car or motorcycle manufacture using floating valves. you can use my valves in a standard road engine as i have for years, i have more than 400 of them out on the road and a few on the track, and so far not one problem, and as i said 60000 miles on my test set. when I designed the first set and had them made the only thing that was important was QUALITY,
richie moore
Registered user
I dont think the information about the standard valves is correct. the stellite process is unlikley to be used in mass production ,as it is not needed when the valve is made up of 2 or 3 parts and friction welded together. and as for them only being good for water cooled engines, I just cant see that it makes any diffrence, the rocker cam or spring pressure will make the diffrence.
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