Hello ! I am brand new to BevelHeaven, so I hope I am not boring everyone
to tears!
I just purchased a 1980 Darmah SD 900 with exhaust pipes of dubious origin.
I want to change them to Contis, and am wondering what to do with the
settings of the 32mm carbs ? The second question is: If I also replaced the
32's with 40mm carbs, in conjunction with the Contis, would I be sacrificing
a great deal of mid-range power to simply boost top-end speed ?
Any suggestions would be greatly appreciated.
Thank You,
GirardFox
What Carb set-up when changing over to Contis ?
- BevHevSteve
- SITE OWNER
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- Joined: Wed Mar 10, 2004 8:53 pm
- Location: Lafayette, California
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conti..
Hi Girard,
You should probably get some K&Ns or some nice trumpets on the carbs after doing a rebuild on your carbs to clean them up, fatten the main 1-2 steps, you might need to go a half step on the needle by using a washer. It is a trial and error thing depending on alot of variables [altitude, condition of motor, condition of carbs etc] Just start with one size up on the mains initially.
Going to 40s is a possability, can you verify that the intake manifold stud spacing measured center to center is 58mm? If so then you can still get intake manifolds for the PHM carbs if the spacing is 53mm then it gets difficult to find the right manifold that would work.
40s are great for top end but around town/low speed riding can get difficult to deal with. I have 40s on my bevel drive - but the motor is worked and is more of a race motor than a street motor. I get used to keeping it at higher revvs, which in my opinion you should do anyways,
It is more common to go from 32 to 36 as it is a straight bolt on proposition. No other changes req'd.
Unfortunately you can;t find new PHF36 AS/AD carbs [the original kind with a clamp on mount] but I can get you new PHF36 carbs that use a rubber manifold which slips over your stock intake manifold. They come with stainless steel hose clamps as well @ $490/set.
http://www.bevelheaven.com/stuff-for-sale-phf.htm
Or get a new set of 40s and I can find some manifolds for you as well [they are not cheap though] and you will also need different throttle cables.
http://www.bevelheaven.com/stuff-for-sale-phm.htm
You will find that the 36 carbs are easier to ride with more of the time compared to going up to 40s.
Did your contis arrive by now?
You should probably get some K&Ns or some nice trumpets on the carbs after doing a rebuild on your carbs to clean them up, fatten the main 1-2 steps, you might need to go a half step on the needle by using a washer. It is a trial and error thing depending on alot of variables [altitude, condition of motor, condition of carbs etc] Just start with one size up on the mains initially.
Going to 40s is a possability, can you verify that the intake manifold stud spacing measured center to center is 58mm? If so then you can still get intake manifolds for the PHM carbs if the spacing is 53mm then it gets difficult to find the right manifold that would work.
40s are great for top end but around town/low speed riding can get difficult to deal with. I have 40s on my bevel drive - but the motor is worked and is more of a race motor than a street motor. I get used to keeping it at higher revvs, which in my opinion you should do anyways,
It is more common to go from 32 to 36 as it is a straight bolt on proposition. No other changes req'd.
Unfortunately you can;t find new PHF36 AS/AD carbs [the original kind with a clamp on mount] but I can get you new PHF36 carbs that use a rubber manifold which slips over your stock intake manifold. They come with stainless steel hose clamps as well @ $490/set.
http://www.bevelheaven.com/stuff-for-sale-phf.htm
Or get a new set of 40s and I can find some manifolds for you as well [they are not cheap though] and you will also need different throttle cables.
http://www.bevelheaven.com/stuff-for-sale-phm.htm
You will find that the 36 carbs are easier to ride with more of the time compared to going up to 40s.
Did your contis arrive by now?
Steve Allen (925)798-BEVL[2385] Ride'm, Don't Hide'm
Ducati/Euro Spares -> https://Store.BevelHeaven.com