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BDL belt primary

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Old Oct 7, 2022 | 02:57 PM
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Default BDL belt primary

I’m looking to buy a primary belt drive for my 80” UL project.
BDL makes two models that they say fit a closed primary, one is the 62-39TK-1 which is a 8mm belt with 62 teeth on the clutch basket and 39 teeth on the motor, the other one is the 47-31TK-1 which a 11mm belt with 47 on the clutch and 31 on the motor.
I sure could use some advice on the pro and cons of both.
 

Last edited by The Turk; Oct 7, 2022 at 03:03 PM. Reason: Wrong info
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Old Oct 7, 2022 | 03:28 PM
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The different tooth count are how they get the spacing right for each available belt size, actual drive ratio's are close. 1.59 for the 8mm and 1.51 for the 11mm. UL isn't going to throw enough power to be an issues for either. You'll be able to adjust the belt correctly for either with a tin primary setup.

Run the 11mm in my shovels.
 
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Old Oct 7, 2022 | 03:42 PM
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Thanks for the reply
Do you (or anyone) think either would have any fitment issues using a stock style primary?
 
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Old Oct 7, 2022 | 03:51 PM
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Your bike still has tins and the trans is how you adjust the primary chain isn't it ? If so any belt system is a drop in. Clearances' inside can't say never set one up with closed tins, but shouldn't be any issues

On the later aluminum primary bikes you did run into issues sometimes with being too tight with 8mm belts.
 
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Old Oct 7, 2022 | 03:58 PM
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I’m still gathering parts for the build, I plan on using a OEM style tin.
I’m going to order the 47-31TK-1 with the 11mm belt.
Thanks for the advice.
 
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Old Oct 7, 2022 | 06:36 PM
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I put one on my 62 with tin primary and have one sitting here to go on the 48 with tin primary. On the 62 the inner primary rubbed the back side of the clutch basket so I "reworked" it to make it happy.
 
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Old Oct 7, 2022 | 06:48 PM
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I’m not afraid to “massage” a part a little bit to make it fit right.
I ordered the 47/31 11mm belt with the BDL CC-100-S clutch,
I hope those were good choices ...
 
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Old Oct 7, 2022 | 10:07 PM
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Originally Posted by The Turk
I’m not afraid to “massage” a part a little bit to make it fit right.
I ordered the 47/31 11mm belt with the BDL CC-100-S clutch,
I hope those were good choices ...
You get just as good a clutch with Aldo red plates, a Jamjett retainer and the aluminium pressure plate for a whole lot less money.

The BDL is good stuff, bit loud rattle wise but works good.
 
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Old Oct 7, 2022 | 10:21 PM
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Originally Posted by TwiZted Biker
You get just as good a clutch with Aldo red plates, a Jamjett retainer and the aluminium pressure plate for a whole lot less money.

The BDL is good stuff, bit loud rattle wise but works good.
Alto and Ram Jett....autocorrect is not your friend.
 
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Old Oct 7, 2022 | 10:38 PM
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Now you tell me... already pulled the trigger on the BDL.
I appreciate your guys advice, I haven’t built a Harley in over 30 years so I need a little help picking the right parts.
 
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