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Resistance on 1955 R25/3 ignition coil

I'd get Vech's recommendations, but here's what I'm doing on my R25/2 based upon my latest notes. In the engine, I use a Golden Spectro 10w40. Generally I think the manual calls for a 40W non detergent for summer and 30W for winter. The transmission has was appears to be a Castrol 40W oil...this one puzzles me as to why I chose that. Normally transmissions have gear oil in them but on general terms a 90W gear oil has the same viscosity as a 40W engine oil. In the final drive, I'm running a GL4 85W90 gear oil. I believe I got that from Vech.

Vech takes the position that a hypoid GL5 gear oil is bad for BMW transmissions and final drives. The reason is that the high Sulphur content can attack yellow metals. In his tech article, he says that before 1992, GL5 can damage the brass and bronze in the transmission. I think the story goes back to maybe some Volvo's that had this happen to them. I suppose there are varying Sulphur content in GL5 products, so maybe some are worse than others. I've run off-the-shelf GL5 gear oil in my /7 for 100K miles and haven't noticed any issues.

http://www.benchmarkworks.com/articles/tech/gearoil.html
 
Thanks Kurt

I'd get Vech's recommendations, but here's what I'm doing on my R25/2 based upon my latest notes. In the engine, I use a Golden Spectro 10w40. Generally I think the manual calls for a 40W non detergent for summer and 30W for winter. The transmission has was appears to be a Castrol 40W oil...this one puzzles me as to why I chose that. Normally transmissions have gear oil in them but on general terms a 90W gear oil has the same viscosity as a 40W engine oil. In the final drive, I'm running a GL4 85W90 gear oil. I believe I got that from Vech.

Vech takes the position that a hypoid GL5 gear oil is bad for BMW transmissions and final drives. The reason is that the high Sulphur content can attack yellow metals. In his tech article, he says that before 1992, GL5 can damage the brass and bronze in the transmission. I think the story goes back to maybe some Volvo's that had this happen to them. I suppose there are varying Sulphur content in GL5 products, so maybe some are worse than others. I've run off-the-shelf GL5 gear oil in my /7 for 100K miles and haven't noticed any issues.

http://www.benchmarkworks.com/articles/tech/gearoil.html

Thank you for the info. What battery are you running? Bike came with a blitz 12ah but unfortunately is toast. :(
 
Your bike is a 6v system right? I wouldn't think a 12v is correct or would work.

Mine is 6v and I'm on my third battery since I've had the bike. I think I had a Blitz to start with, but that stopped working and left me stranded on the road. I got another simple 6v battery from Vech. Both of these two batteries were the maintenance type which required watching the fluid levels. This second battery had a serious issue with sloshing battery acid out and onto the bike. I tried everything I could to keep this from happening but nothing worked. I even tried gluing some pipettes from spray cans to the opening in the fill caps...see picture. The hope was that it would be harder for the acid to climb that high and escape. Didn't work. I talked to Vech and he said they don't sell these type of small footprint batteries for the singles because they are damaged by the bike's vibration. He didn't recommend any of the maintenance-free batteries either because they were weak internally and the vibration would damage the battery.

On the German forum, I posed this problem and was told that several were running a maintenance-free battery and had been for a number of years. So, I decided to take a shot and bought a Duracell 6v 5ah battery from Batteries Plus. It's really small and I had to support it with some foam under and behind to keep it away from the battery tray. I also had mounted some post extensions which allows for quick release from the bike's harness. It's mounted pretty ugly...just some big zip ties to keep it in place. But it's worked for nearly 4 years. I suppose the ideal thing for me to do is get an older battery (I wish I still had my Blitz) and hollow out the inside so the Duracell could be stuffed inside. Then it would look much better installed.BatteryPipes.jpgDuracellBattery.jpg
 
Great Info!

Thanks Kurt,
It is a 6v battery (12 amp hour) Since I have the blitz and love how it looks I will try your great suggestion And locate the Duracell battery you specc’d inside it :)

Dave
 
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