Lower rpm’s at higher speed help

Discussion in 'General Harley Davidson Topic' started by rick1062, Dec 20, 2010.

  1. rick1062

    rick1062 Active Member

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    I need to pull my primary gearcase to fix a leak at the trans shift shaft seal. I am working on a 2002 Dyna Wide Glide (fxdwg). I have heard of some people increasing the size of the forward belt drive pulley. I don’t want to buy a new belt, so if I go this way, how large can I go and not have to get a longer belt.

    Also, I have seen some kits that use a larger compensator sprocket and primary chain to get a similar outcome.

    So I am looking for input on either of these methods. What will the outcome be? Are people happy that have made these conversions? What are the pros and cons of each?

    If I am ever going to make the change, it makes sense to do it now while everything will be apart to do the job, for either conversion.

    Any comments will be appreciated.
    :eam
     
  2. BUBBIE

    BUBBIE Well-Known Member

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    I would go with the engine sprocket IF I did the job.. A couple of teeth more on the engine would change gear ratio UP in all gears.

    The rear wheel pulley would be easiest to change out if going that way.. I think 2 teeth (bigger-smaller) common.... HD parts would Know how to answer and Probably have needed information. (not sure, just a guess)

    The engine would be the one I would see about... Adding a sprocket by two teeth there would Gear up the bike a little..

    I DOUBT I would like a bike Geared up,,,Even a little. I could SEE going LOWER geared tho'.

    The low gear on your bike is tall as it is. The LOSS of power would BE Noticed by making it higher.. Probably having to slip the clutch more when starting out Especially when riding double..

    I would suggest to JUST go with a conversion Tranny or Gear set.. TQ1 is doing a 6 speed conversion and has done a Whole 6 speed box...

    This is the way I went on my 2000 FXDS ; by putting a rev-tec 6 speed gear set in it...TODAY i would probably go with the whole Box change-out as Prices have come down on some of the pretty good model 6 speed trannys out there..

    The LOSS of power on higher gearing like mentioned here Even with a BIG motor the LOSS would be noticed,,,, to me It's a BAD Idea and I would Not recommend doing it...

    MY Opinion given, like you asked

    signed....BUBBIE
     
  3. rick1062

    rick1062 Active Member

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    I don't ride two up very often, so that is not a big an issue is it might be.

    What about the speed o meter? Is there something that can be done to make the speed o meter accruate after this sort of conversion??
     
  4. BUBBIE

    BUBBIE Well-Known Member

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    I think anything like engine Less/More Teeth, doesn't affect the spedo. The other on the belt I think would have to be done with a electrical box install, And adjusts to compensate for the gear change on the belt pulleys.

    I bought a elec. unit to do a 6 speed conversion in a 2000FXDS, it just plugged in-between the Spedo wires under seat and did the re-calibration setting just fine.

    The engine with 2/4 more teeth on the main sprocket would be an easy way to go and you could always change it back IF you wanted..

    To me the primary sounds like a place to check for gearing off the motor..

    signed....BUBBIE
     
  5. rick1062

    rick1062 Active Member

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    Thanks Bubbie,

    That makes sense. If I persue this, I agree that the compensator sprocket is the best place. Now to decide if I want to do it or not. And if I don't like it, the compensator sprocket would be much easier to change back.
     
  6. Hoople

    Hoople Account Removed

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    If you make the change within the primary, the speedo won't change. It will be the same as it is now.
     
  7. BUBBIE

    BUBBIE Well-Known Member

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    ***************************************
    Just for Open Information here;
    Geezer wants to go Lower geared.
    His stock compensator off his bike is 34 tooth. and thinking to take his rpm Down, so he can use 6th gear doing the speed limit.

    Taking the diameter to a smaller size = less 2/4 teeth would probably give him the lower ratio he needs. I figured 4 teeth would give him 300 RPM to change his speed. So while in 6th gear doing 2800/2900 rpm and doing 70. he could be doing 70 at 3100/3200 RPM... Then slowing down to speed limit and able to use 6th gear.

    SO You going the other way,Larger, More teeth to Gear UP by the same amount would probably work..2/4 teeth

    (*X*) Question is Where Do WE Get Sprockets that would fit a HD?????

    Chopper showed us one that is used in racing but way too low a ratio for street use.

    I suggested to geezer (he knows a shop)to machine OFF his sprocket to a desired size for another to fit the boss housing. Then having a replacement sprocket made to work on that , USING the original HD Boss and welding the New sprocket on to it. Makes sense to me**...
    (**I'm a retired weld shop/machine, lathe but lathe sold)

    Geezer and I discussed the ? about IF the HD's engine sprocket is hardened or heat treated in any special fashion? Don''t know.... BUT that could be done after made like I suggested above.

    The cutting of gears by lazier or flame/water/elect. torch has been used for years in my trade and what I have ordered, Pre-made to replace only the outer part on the Big and Hard to remove gears, Just leaving them on the machine and renewing the worn teeth to match the original equipment so labor is cutting and welding the new part made to fit on/over the existing gear face. Why not on the Harley ????

    Now I don't know of any shops around that do this(cut sprocket gears) Now but I'll see how geezer comes out with His project and go from there..

    (*X*) Maybe some one out there KNOWS where to get HD's pre-made so we don't have to go and fabricate one.

    We're ALL EARS :newsmile048:

    signed....BUBBIE
     
  8. Jack Klarich

    Jack Klarich Expert Member

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    Any good machine shop could do this with CNC machines, the problem would be the programming- set up unless ordering by the basket load IMO, my neighbor is quite good @ this I will run it past him he works for Northrup Grumann as tool and die and set up man
     
  9. tlyoungb

    tlyoungb Junior Member

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    Wow...This is all very interesting, but if you can get your hands on the latest issue of American Iron Magazine, you will see a 4 page article with pictures on this very thread. The title is called Gear Ratios. Pretty detail, and can get confusing, but very good reading.

    January 2011 issue. Harley Gearing: What's best for you and why.
     
  10. Jack Klarich

    Jack Klarich Expert Member

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    Always good info , I have had a subscription since the begining, I like this magazine, you can leave it laying out and the young ones can look at it cause it is a clean magazine IMO