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Mcgee
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Port Townsend Wa.
Joined: 12/07/2014
Posts: 14

Howdy all! As stated I have a 74 r90. I bought it a year ago and have enjoyed riding it. Plus I have been learning about these bikes and do all my own maintenance. The oil pan looks to be an after market deeper one. It has a step in it to accommodate the center stand. The dip stick is only 10 7/8 inches to the tip measured from the bottom of the threads. Max is 9 3/4 and min is 10 3/4 inches. Even tho it appears to have a larger oil pan, does the measurements of this dip stick seem like the right one? Some of the research I have done it appears this is not the right dip stick for this engine. And do I need to get a longer one for the oil pan.

I would appreciate any thoughts on this.

schrader7032
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VBMWMO #7032
San Antonio, TX
Joined: 10/27/2006
Posts: 6427
Anton has a great page on

Anton has a great page on this:

http://www.largiader.com/tech/oilpan/

It would appear that you have part 11 43 1 252 661 which is around the 9.75 inches you indicate...that's for a /5.

You have three choices regarding oil level with a deep oil pan. 1) Using the original dip stick, fill to the same max mark. Pro - more oil for potentially better cooling (doubtful). Con - no improvement in air volume above the oil which reduces windage and generation of oil misting. 2) Use a longer dip stick so that you put the same amount of oil in as the stock engine, roughly 2 liters. Pro - big increase in air volume above the oil level. Con - no increase in oil volume for potentially cooling. 3) Somewhere in between 1) and 2). Number 3) seems like the best option to me.

Now the issue is finding a way of measuring to 2) or 3) if that's what you choose.

__________________

Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

Mcgee
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Port Townsend Wa.
Joined: 12/07/2014
Posts: 14
Thank you for your response

Thank you for your response to my question, it was very helpful. Maybe I should pull the pan and see if the pick-up tube has been lowered for the 2 liters of oil in the larger pan. Then when I refill the oil, put the correct amount in and then figure out what the dip stick says and go from there.

schrader7032
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VBMWMO #7032
San Antonio, TX
Joined: 10/27/2006
Posts: 6427
Sounds like a good plan.

Sounds like a good plan. It's important to be sure the extension is solidly attached...it could suck air if not sealed properly.

__________________

Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

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