Final gears

Discussion of the Genuine Buddy, Hooligan, Black Jack and other topics, both scooter related and not

Moderator: Modern Buddy Staff

Post Reply
Azspeeda
Member
Posts: 3
Joined: Sat Oct 29, 2022 11:27 pm
Location: Golden Valley AZ

Final gears

Post by Azspeeda »

New to the forum...Had a 2007 Blur 15 years ago...Son's hanging on to it...still on the road...PGO makes a really good product...so today I picked up a 2008 Buddy 150...with just 318 miles...nope not a typo... runs like it just left the showroom.. I never get deals so good for me...so instead of changing tire size has anyone changed out the final gears on their unit...wondering how the swap went and the verdict...Thanks Mark





..
Last edited by Azspeeda on Sun Oct 30, 2022 1:25 pm, edited 2 times in total.
Therealslimshaggy
Member
Posts: 49
Joined: Thu Sep 22, 2022 2:50 am
Location: Dallas
Contact:

Re: Final gears

Post by Therealslimshaggy »

What exactly would you like to know after a final gear change? Higher top speed? Lower rpm’s? If you got the buddy 150 it’s a special model. Most come in 125 or 170. I have the 170. I swapped in 14g dr pulley sliders which give a top speed and cruising rpm faster than the buddy is designed for. I did it without changing gear ratio and instead going to sliders. Much better than rollers. It pulls from 50 to 65 and tops out at 70. Really low rpm’s in the 60s. The problem I’m having is the tires are just too small to go those speeds. I’m looking to upgrade to oversized tires. I’m sure I could go 75 or 80 with more modifying but I don’t even like how it handles at 55 now so what’s the point? There’s lots to modify before the final gear ratio. Like tires that don’t break your back and remain stable above 55.
Yamaha Aerox 155, Genuine Roughhouse 50, Genuine buddy 170i, Yamaha Cygnus 125, Honda grom 125, Suzuki address 110 (uk110), Yamaha cuxi 115, Yamaha BWS 100 2t, Yamaha R6, Honda CR125, Kawasaki KX 500
Azspeeda
Member
Posts: 3
Joined: Sat Oct 29, 2022 11:27 pm
Location: Golden Valley AZ

Re: Final gears

Post by Azspeeda »

Wondering about how much lost acceleration and how much gain in top end with a stock power plant people have realistically achieved with this modification...and thanks for your reply!
scootERIK
Member
Posts: 714
Joined: Thu Jul 12, 2012 3:40 am
Location: Lake Geneva, WI

Re: Final gears

Post by scootERIK »

How fast is it going now and how much more speed are you looking for? With only 318 miles your scooter isn't broken in yet so you should pick up a few more MPH as it breaks in, it seems most Buddies don't hit top speed until after ~1,500 miles. Many people have picked up 1-3 MPH by adding a windshield so that might be an option.

I don't recall that many people changing their final drive gears on here. Of those I don't remember any really positive reviews. If anyone has done a final drive gear ratio change with good results I would be interested to hear about it.
User avatar
Kaos
Member
Posts: 4892
Joined: Mon May 19, 2008 5:39 pm
Location: Portland, OR

Re: Final gears

Post by Kaos »

What're you trying to achieve? Most transmission tuning is easier to do with variator weights and clutch springs. There's really not a lot of reason to change out the rear gears unless you're going with a wildly different rear wheel size and modding the bike so it'll fit.
Azspeeda
Member
Posts: 3
Joined: Sat Oct 29, 2022 11:27 pm
Location: Golden Valley AZ

Re: Final gears

Post by Azspeeda »

Thanks for the feedback... what am I looking to achieve... good guestion...I had a blur back in the day...did the cvt stuff on it but really didn't gain much...I would like a scooter that can do a true 55/60 on fairly good roads... But not to suffer greatly at stoplights... haven't driven it get except for doing figure 8s in yard...2 miles worth in the Arizona desert...getting use to those little tires, really guick steering...my last bike was a Kawasaki Concours...so big difference...getting up in age so back to scootering...I did order a Cuppini windscreen last night....just planning a plan...again thanks for all the great feedback...
User avatar
Kaos
Member
Posts: 4892
Joined: Mon May 19, 2008 5:39 pm
Location: Portland, OR

Re: Final gears

Post by Kaos »

A buddy 150 should do 60 bone stock. I'm 6'3" 190lbs and my Buddy 125 could do that bone stock, after putting some Dr Pulley sliders in it it kept about the same top speed and gained a bit of acceleration... I don't recall now what weight I put in. It's been EONS since it was stock but I'm sure a quick search should tell ya.
sc00ter
Member
Posts: 1140
Joined: Sun Mar 30, 2008 9:17 pm
Location: Norfolk VA

Re: Final gears

Post by sc00ter »

A friend of mine had a modded Buddy 125 and wanted more top end. He tracked down the ratio that was used in the Buddy Psycho limited edition. I don't recall the exact numbers but he got more top speed, and with a aftermarket variator we got the low end dialed back in. I asked him about it but he sold the modded Buddy (had a bbk kit on it) and included the service manual that had all our notes written in it.

Now this was done well before the Buddy 170i existed so I'm not sure what ratio the 170i uses. But I recall tracking the Psycho gear ratio down was a PITA, hence our handwritten notes with part numbers in that service manual.
scootERIK
Member
Posts: 714
Joined: Thu Jul 12, 2012 3:40 am
Location: Lake Geneva, WI

Re: Final gears

Post by scootERIK »

sc00ter wrote: Tue Nov 01, 2022 1:30 pm A friend of mine had a modded Buddy 125 and wanted more top end. He tracked down the ratio that was used in the Buddy Psycho limited edition. I don't recall the exact numbers but he got more top speed, and with a aftermarket variator we got the low end dialed back in. I asked him about it but he sold the modded Buddy (had a bbk kit on it) and included the service manual that had all our notes written in it.

Now this was done well before the Buddy 170i existed so I'm not sure what ratio the 170i uses. But I recall tracking the Psycho gear ratio down was a PITA, hence our handwritten notes with part numbers in that service manual.
I think the Psycho was geared for better acceleration? From what I remember there are three different final drive gear ratios in the 4t Buddies. The Psycho gear ratio, the Buddy 125 gear ratio, then the 150/170 gear ratio. The Psycho was geared for more acceleration than the 125 and the 150/170 gears were geared for a higher top speed.

But it can still make sense that the Psycho gears could increase top speed since they might put the motor in a better spot in the power curve, I know my Buddy lacks the power to go faster so gearing it for better acceleration would probably increase my top speed. I loss top end speed when I run the 130/70-10 or when I run heavy roller weights.

But I could be wrong, since the search function doesn't work that great I am going from memory.

*There is an old thread on here that has all the gear ratios listed but I will need more time to find it.
**Talking about gearing is a little hard with the higher or lower and higher or shorter so I just used acceleration and top speed to make it easier for me to describe.
sc00ter
Member
Posts: 1140
Joined: Sun Mar 30, 2008 9:17 pm
Location: Norfolk VA

Re: Final gears

Post by sc00ter »

Exactly ERIK. I wish I had that service manual with the notes added. Would make this while mystery easier to solve.
scootERIK
Member
Posts: 714
Joined: Thu Jul 12, 2012 3:40 am
Location: Lake Geneva, WI

Re: Final gears

Post by scootERIK »

I might have found the final drive gear ratios. Theses are from a post back in 2014.

Psycho 9.5 to 1
125 9.07 to 1
150/170 8.25 to 1
Therealslimshaggy
Member
Posts: 49
Joined: Thu Sep 22, 2022 2:50 am
Location: Dallas
Contact:

Re: Final gears

Post by Therealslimshaggy »

scootERIK wrote: Tue Nov 01, 2022 3:04 pm
sc00ter wrote: Tue Nov 01, 2022 1:30 pm A friend of mine had a modded Buddy 125 and wanted more top end. He tracked down the ratio that was used in the Buddy Psycho limited edition. I don't recall the exact numbers but he got more top speed, and with a aftermarket variator we got the low end dialed back in. I asked him about it but he sold the modded Buddy (had a bbk kit on it) and included the service manual that had all our notes written in it.

Now this was done well before the Buddy 170i existed so I'm not sure what ratio the 170i uses. But I recall tracking the Psycho gear ratio down was a PITA, hence our handwritten notes with part numbers in that service manual.
But it can still make sense that the Psycho gears could increase top speed since they might put the motor in a better spot in the power curve, I know my Buddy lacks the power to go faster so gearing it for better acceleration would probably increase my top speed. I loss top end speed when I run the 130/70-10 or when I run heavy roller weights.

Can you post a picture or elaborate more on the 130 70 10 tire on the buddy? I really want to run a bigger rear. That’s the size I run on my roughhouse and it’s been doing a fine job of absorbing bumps but the buddy is just too stiff with the 100 90 10 rear on it now. If the 130 is too big would also go 120 with city grip.

About the dr pulley sliders I’m using on my buddy 170. I got the 14g weight. Main difference between sliders and rollers in the low rpm between 50-60. Stock rollers are 14g so I decided to just go with 14g sliders. But with sliders the weight is distributed differently during centrifugal force. The change I have experienced is rollers kind of climbed through rpm’s steadily, but with the sliders it does something different. My 170 is completely stock other than the slider modification. So what it does now is accelerate about the same as stock up until 45-50mph. At the point the rpm’s are a little high but when you go wop at 45-50 (wide open throttle) the rpm’s drop a lot and you can find a low rpm cruising speed somewhere between 50-60. Lower rpm’s than stock in that speed with the 14g sliders. After 60 rpm’s steadily climb until max speed at 70 and feels very buzzy. I feel I definitely need to upgrade to better brakes and bigger tires above 50mph. I’m looking at the 220m rotor and braided front brake line along with a mag front wheel fitted on newer buddy’s which might be lighter and so stop faster. A 100 80 10 and 120 70 10 rear Michelin city grip.
Yamaha Aerox 155, Genuine Roughhouse 50, Genuine buddy 170i, Yamaha Cygnus 125, Honda grom 125, Suzuki address 110 (uk110), Yamaha cuxi 115, Yamaha BWS 100 2t, Yamaha R6, Honda CR125, Kawasaki KX 500
scootERIK
Member
Posts: 714
Joined: Thu Jul 12, 2012 3:40 am
Location: Lake Geneva, WI

Re: Final gears

Post by scootERIK »

Therealslimshaggy wrote: Fri Nov 04, 2022 7:21 pmCan you post a picture or elaborate more on the 130 70 10 tire on the buddy? I really want to run a bigger rear. That’s the size I run on my roughhouse and it’s been doing a fine job of absorbing bumps but the buddy is just too stiff with the 100 90 10 rear on it now. If the 130 is too big would also go 120 with city grip.
For me the the 130/70-10 was a little bit smoother over bumps. A lot of people have run the 130/70 without rubbing. I had one 130/70 that rubbed. I don't know of anyone has run an oversized City Grip so I don't know how well that tire will fit.

Here is a thread that has some pictures - http://www.modernbuddy.com/forum/viewto ... t=130+7010
and this one - http://www.modernbuddy.com/forum/viewtopic.php?t=24149
sc00ter
Member
Posts: 1140
Joined: Sun Mar 30, 2008 9:17 pm
Location: Norfolk VA

Re: Final gears

Post by sc00ter »

For tuning the variator buy 2 sets of tuning rollers. The 2 sets are so you can really fine tune the transmission before committing to your final roller choice. Note there is a slight variance when swapping over to Dr. Pulley. I think its a gram difference down? Anyways, tuning rollers, heat resistant gloves, air ratchet and tons of time and you'l get it dialed in. I know we did the gears first and while the scooter was faster on the top end the acceleration was slower. So I loaned him the upgraded variator from my wifes Buddy to see if we could dial everything back in. My wife wasn't riding at that time so she didn't mind. A few other mods that we did.
Torque spring bearing seat. Forgot the exact name of it but worth the trouble to smooth everything out.
Vented/drilled clutch bell. It also had a knurled inside to help grip better. Off brand that worked great. We even checked the balance and rotational roundness of it at my local machine shop. Was well within spec.
OEM belts are best. The OEM kevlar reinforced ones are nice but they pickup any vibrations and amplify them.
I reached out to my friend but he doesn't remember anything that was done. Best part was I saw the modded Buddy but didn't have time to stop and talk. Only seen it that one time.
Off subject tuning that we also did.
The big valve heads that you see are not the best quality. I took the original head and had my local machine shop (who builds Ducati motors) optimize the valve seating and flow. I used to send them off to Yoshimura for this service but I can walk to my local machine shop. Anyways it made a very noticeable gain in performance. I wanna do my Liberty head one day but I'm to lazy to take it apart.
If your Buddy has a carb you can slightly upjet and swap out the needle slide. My old service manual had all the notes and I don't recall what we did.
My friend did the larger tire swap but it was a TIGHT fit. My wife went with a slightly smaller tire size to lower her Buddy. Funny part was my wifes Buddy was slightly faster than my friends Buddy! Even if they swapped scooters. He swore I saved a tuning secret for her scooter! The motor builds were pretty much identical, same with the overall mods in the transmission. We concluded that Powder/Baby blue color is just faster than black. I miss a Buddy sometimes.....
GenBud170
Member
Posts: 3
Joined: Sat Oct 09, 2021 2:30 am

Re: Final gears

Post by GenBud170 »

Maybe I missed something but I'm not seeing a straight answer. He wants this I believe https://www.rollingwrenchdenver.com/col ... ear-up-kit

What performance gains and losses would he experience?
scootERIK
Member
Posts: 714
Joined: Thu Jul 12, 2012 3:40 am
Location: Lake Geneva, WI

Re: Final gears

Post by scootERIK »

GenBud170 wrote: Sat Nov 05, 2022 7:24 pm Maybe I missed something but I'm not seeing a straight answer. He wants this I believe https://www.rollingwrenchdenver.com/col ... ear-up-kit

What performance gains and losses would he experience?
I don't think the OP is going to get a good answer on this question. Gear ratio changes are not a common mod on the Buddy, at least from what I have read. I remember some people doing it on their 125s with BBK and other mods. I also remember seeing some off these people go back to the stock ratio after riding it for a while. Most of the people doing a lot of modding to their Buddies aren't active anymore.

Since we can't give the OP a good answer we are trying to help by figuring out how fast the scooter is currently and how fast the OP would like it to go. Depending on those answers we might be able to help point them in the right direction, or at least save them some time and money.
Post Reply