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Discussion Starter · #1 ·
How much of a difference in gearing does changing the 34t front drive pulley to a 32t actually make?
On paper, it's not much of a ratio change, but I know that doesn't always tell the whole story.
My 05 350/385 seems to be geared a bit too tall to suit me, and I'm thinking about changing the pulleys.

Allen Dean
Austin,Tx
 

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Allen , just for a comparison. I run a 32 tooth front pulley on my ZZ4 and a 70 mph the tach reads 2100 Rpm's .

Jack
 

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Discussion Starter · #3 ·
Jack, did it help with the around town riding ? On mine at speed from About 40 mph to 50 mph it seems like 1st is too low and o/d is too high.

Allen Dean
Austin,Tx
 

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I put a 32 tooth on my '01 385 and notice a considerable difference. First, I had trouble doing a burnout with my car tire and the 34T. With the 32T, no problem. It does seem like when you're just crusing or Putting as I call it, I want to shift at a lower MPH. However, it is much more responsive and I like it very much. It's a good $100 investment.

I too run around 2100 rpm at 70 MPH and about 2400 rpm at 80 MPH.

Alan
 

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Allen , my bike came new with the 32 tooth front pulley so I have no comparison but I like the lower gear ratio's and have always geared all of my bikes low .

Jack
 

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Discussion Starter · #6 ·
Ok guys..thanks for the input..I'm gonna make the swap.


Allen Dean
Austin,Tx
 

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a1goodboy said:
Ok guys..thanks for the input..I'm gonna make the swap.


Allen Dean
Austin,Tx
It looks like to me if you do much riding between 45 to 60 in OD the converter would slip and over heat.

Adrian
 

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Discussion Starter · #8 ·
I'm hoping the gearing reduction will increase RPM in that speed range to allow the converter to slip less..just seems that for putting around town the gear ratio is too high, and I don't need that tall gearset that's good for 180MPH+....90% of my riding is under 90 MPH.

Allen Dean
Austin,Tx
 

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Are there any of you guys out there who have made the swap from a 34 tooth to a 32 tooth, that have noticed a change in fuel mileage :?:

It's not that we buy the Boss for the fuel mileage. I'm just curious.

Bryan
 

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I don't have any personal experience but have heard (very reliable source) that the swap is comparable to going with the high stall converter over stock converter. I plan to change my 34 out when new engine is ready. :D
 

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I don't know what year Boss started using the 34 tooth front pulley but my 2000 came with a 32 tooth . My bike is very responsive , and when I read some of these post's where someone will say they have a hard time breaking the rear wheel loose , I just can't imagine that . I think anyone that is running the 34 tooth pulley ought to do themselves a big favor and switch to a 32 tooth pulley . You won't be disappointed .

If you really want to be able to pull stumps , put a 30 tooth on the front . I know the one speeds had either a 30 or 32 on them .

Jack
 

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I had a 32 on my single speed and went to a 34. I t dropped my rpm down about 200 rpms if I remember right. I could still spin the tire with the 34.

After I put the 2 speed in I went back to the 32 because I really didn't need the 34 anymore. I gave the 34 to Carb Mike but I'm not sure if he ever put it on or not. If he did then he could tell you the rpm change.
 

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I'm not sure if all 2000's came with the 32 tooth pulley . I think some had 34 teeth .

Lamont , does your bike have the 74 tooth rear pulley or the 80 tooth ?

Jack
 

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Front Pulley I D?

All;

How would I identify the difference between Gates and Dayco front pulleys? Are they uniquely marked, or significantly different width, or tooth pitch?

I have a 38 front, 80 rear Gates (MBH Frame Loop Mod) on a single speed clutch I'm soon converting to a single speed auto with #7 Converter. Think I may want to try a smaller front @ some time and don't want to mess it up.

How many teeth did the single speed auto's have?

Thanks
Ride Safe! HAWK88
Jack Phillips
 

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Jack , are you sure you have a 38 tooth front pulley ? I didn't know the even made one that large . All I've heard of are 30 , 32 and 34 tooth but I really haven't researched it.

Jack
 

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38

Jack;

Yes, Mountain Boss Hoss made a special "Frame Loop Mod" to accomidate the size of the pulley. I guess it was an effort to make it more tractable on the highway.

That contributes to my Boss eating clutches because you have to slip the darn thing to about 30ish MPH. The smaller diameter of the P245/50ZR15 Dunlap made it much easier to ride around town, but significantly "buzzed" the RPM's up on the "I" roads. I was really blessed to get so many mods and upgrades. I think I would like a smaller pulley for Daytona type stuff, and the 38 for highway. 2 speed out of the budget.
==========================================
1997 Boss Hoss
350/355 horsepower
Single Speed clutch with MBHC frame loop conversion and
38 tooth front pulley. (3000 rpm = 72 mph)
16,700 miles. JUST TRADED!!!

NEW candy apple red metallic paint with custom race checkerboard graphics.
2004 front & rear fenders and side panels.

Options Include: 2003 inverted front end, chrome upper and
lower air dams with Lazer driving lights, new style dual exhaust, 230 Avon rear tire,
Mini Ape handlebars, Corbin seat, Aldan rear shocks, chrome brake calipers,
Duece turn signals, chrome gauge bezels, mini tack, chrome reserve fuel tank
with electronic switch valve, Ness taillight license plate bracket, Landmark fuel caps,
electronic speedometer, chrome fan, chrome rear brake master cylinder and much more!!!
This is a local trade and has been completely serviced and is ready to ride!!!

Ride Safe!
HAWK88
Jack Phillips
 

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I just counted the teeth on my year 2000 zz4-2 speed. It is 38 front and 80 rear! Cheese, I thought that 32 or 34 were pretty much standard for the 2speed?? I was going to switch to a 32 front till I actually counted the front sprcket. 32 would probably be toooo low. I may switch to a 34 tooth (from my 38 tooth). DOes this sound reasnoble based upon my 80 teeth rear sprocket? I am not looking for 200 mph bike, rather I want 100-120 or so with reasnoble rpm at about 70 mph.

Milos
 

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I bought my 2000 new ,and it has a 32 tooth front pulley . with that 38 tooth what rpm do you turn at 70 mph in 2nd gear ?

Jack
 

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Discussion Starter · #20 ·
I ordered a 32 T for my 05 ZZ4 and it's waiting for me at Boss Hoss-Houston. I'm taking it over there this coming Sat to have them put it on.
I think mine has a 34T on it now..when I get it back I'll let you know how much difference it made in the overall gearing.
Right now at 70 mph, mine is spinning about 2050 rpm, but I've got the Avon 300 tire on it too.


Allen Dean
Austin,Tx
 
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