Sb50p sticker bomb build

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Chubbyfunkmonkey
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Sb50p sticker bomb build

Post by Chubbyfunkmonkey » Mon Nov 06, 2017 2:37 pm

Hello? I'm a noob to hondaspree.net and this is my first post. A couple of months ago I got a 1989 sb50p as a trade for some work I did getting a scooter running for someone in my neighborhood. It was in really rough condition as it sat for seven years or so and wasn't running when it got put away. I opened it up and found that the previous owner had tried to modify the intake for more power but had leaned it out to the point that it wouldn't even start. I replaced the intake with a foam filter and re jetted the carb. It runs 25-30mph with decent acceleration but I'm hoping to get it past 30 with some more work.
1989 sb50p
2005 ruckus 50cc custom
2009 ruckus 125cc 4speed

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Re: Sb50p sticker bomb build

Post by eclark5483 » Mon Nov 06, 2017 3:41 pm

I'm assuming by INTAKE you mean the air filter... try http://hondaspree.net/phpBB3/viewtopic.php?f=4&t=34653
Indian Motorcycle tech @ Polaris Industries, B.A. Information Technology, A.A. Engineering
3 Sprees
1 ATM50-A1
1 Indian AMI-50
World's Greatest Spree: https://www.youtube.com/watch?v=lU49lL_Xx4s
Want to make a Spree engine go fast? CLICK HERE: LINK

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Re: Sb50p sticker bomb build

Post by Chubbyfunkmonkey » Mon Nov 06, 2017 4:10 pm

thats correct. scrapped the stock setup for a UNI.

ImageIMG_1682 by chubbyfunkmonkey, on Flickr
Last edited by Chubbyfunkmonkey on Tue Nov 07, 2017 12:29 am, edited 4 times in total.
1989 sb50p
2005 ruckus 50cc custom
2009 ruckus 125cc 4speed

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Re: Sb50p sticker bomb build

Post by Chubbyfunkmonkey » Mon Nov 06, 2017 6:37 pm

i cut the exhaust in half to see how it was set up and found this. The exhaust gets turned around multiple times before exiting through the tiny exhaust tip. I'm thinking i can increase flow by welding an old propane cylinder on to the stock pipe minus the muffler

ImageIMG_1627 by chubbyfunkmonkey, on Flickr
Last edited by Chubbyfunkmonkey on Tue Nov 07, 2017 12:30 am, edited 2 times in total.
1989 sb50p
2005 ruckus 50cc custom
2009 ruckus 125cc 4speed

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eclark5483
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Re: Sb50p sticker bomb build

Post by eclark5483 » Mon Nov 06, 2017 7:50 pm

First of all, can't see the pic from photobucket, and second, this is a 2 stroke, your pipe is tuned to the engine. You'll gain a whole lot of nothing doing so.
Indian Motorcycle tech @ Polaris Industries, B.A. Information Technology, A.A. Engineering
3 Sprees
1 ATM50-A1
1 Indian AMI-50
World's Greatest Spree: https://www.youtube.com/watch?v=lU49lL_Xx4s
Want to make a Spree engine go fast? CLICK HERE: LINK

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Re: Sb50p sticker bomb build

Post by Chubbyfunkmonkey » Mon Nov 06, 2017 8:22 pm

Sorry, the images are showing up on my end, but i'll add some links, hopefully they'll work, let me know. As far as the custom exhaust goes i picked the propane tank because of the threaded neck. I think I'll be able to fabricate a number of baffles and tune the exhaust instead of trying to tune the engine. This is my first 2 stroke but at top speed it sounds like it is being limited by an overly restricted muffler. The gains made by using the foam filter where minimal and only really affected performance at 10-20mph which I'm hoping is because the exhaust is the weak link.
1989 sb50p
2005 ruckus 50cc custom
2009 ruckus 125cc 4speed

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Re: Sb50p sticker bomb build

Post by eclark5483 » Mon Nov 06, 2017 8:37 pm

If you wanna think that, go right ahead, good luck.
Indian Motorcycle tech @ Polaris Industries, B.A. Information Technology, A.A. Engineering
3 Sprees
1 ATM50-A1
1 Indian AMI-50
World's Greatest Spree: https://www.youtube.com/watch?v=lU49lL_Xx4s
Want to make a Spree engine go fast? CLICK HERE: LINK

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Re: Sb50p sticker bomb build

Post by Chubbyfunkmonkey » Mon Nov 06, 2017 9:07 pm

Worse comes to worse I swap one of my ruckus motors. I just can't settle for less than 30mph. I'll weld it tomorrow and update my findings. i feel pretty good about it after seeing the inside of the stock muffler. To be honest this is my first 2 stroke build so I expect there to be a bit of a learning curve. With not much in the way of after market exhausts my options are limited, not to mention the propane tank was only $3.
1989 sb50p
2005 ruckus 50cc custom
2009 ruckus 125cc 4speed

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Re: Sb50p sticker bomb build

Post by Meatball » Mon Nov 06, 2017 9:50 pm

Swap in a better motor and never look back. Not having much for aftermarket support for your motor should tell you something. Look for a variated AF05 or even better, an AF16. Ditch the Ruck motor swap idea...its a bad one.
I need to find some new haters...the ones I have are starting to like me.

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Re: Sb50p sticker bomb build

Post by Chubbyfunkmonkey » Mon Nov 06, 2017 10:01 pm

I have 3 modified ruckus motors, I need to do something with them. I'm looking at dropping one in an old express sr, but that would be a couple builds away.

ImageIMG_1686 by chubbyfunkmonkey, on Flickr

also photobucket sucks, any suggestions?
Last edited by Chubbyfunkmonkey on Tue Nov 07, 2017 12:29 am, edited 3 times in total.
1989 sb50p
2005 ruckus 50cc custom
2009 ruckus 125cc 4speed

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Re: Sb50p sticker bomb build

Post by eclark5483 » Mon Nov 06, 2017 10:24 pm

Would really suggest you learn how a 2 stroke works, and how sound waves play a key role in the exhaust and how it gives you more power. Your going blindly into it on a hunch, and worse yet, you are attempting it with an AF05. No need to report back, we already know what will happen. Seriously consider meatballs suggestion.
Indian Motorcycle tech @ Polaris Industries, B.A. Information Technology, A.A. Engineering
3 Sprees
1 ATM50-A1
1 Indian AMI-50
World's Greatest Spree: https://www.youtube.com/watch?v=lU49lL_Xx4s
Want to make a Spree engine go fast? CLICK HERE: LINK

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Re: Sb50p sticker bomb build

Post by Chubbyfunkmonkey » Mon Nov 06, 2017 10:40 pm

Well, I do know how a 2 stroke works and I can tell you that the propane tank will certainly redirect more "sound waves" back at the exhaust pipe than the stock one did. The stock exhaust only works by limiting the overall volume of exhaust expelled and not by timing the echo. I know I'm new to this forum and maybe I don't have a lot of practical 2stroke experience but I got a feeling I'm on the right track. If it all goes to crap we can have a laugh at what a stupid idea it was, but if it works 35mph here I come. Lets say 32mph just to be realistic ;)

ps: this was a free scooter I'm just looking to have fun with it, on the cheap
1989 sb50p
2005 ruckus 50cc custom
2009 ruckus 125cc 4speed

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Re: Sb50p sticker bomb build

Post by Meatball » Mon Nov 06, 2017 11:00 pm

Your moxy is admirable, no doubt. I support anyone trying new things since thats how progress happens. My point was that youre using good effort on a bad motor.....to modify. The AF05 Spree/SB50 motor is a great motor that performs very well at doing what it was designed to...go 30mph. Having extensive knowledge in modifying Ruck motors, you understand how vital the CVT is to performance. Unfortunately, this motor does not have this key feature. It also doesnt respond very well to modifications that deviate from the stock settings.

Get a Dio motor....modify THAT....spank modified Rucks all day and wonder why you didnt do this a long time ago. :ndance:
I need to find some new haters...the ones I have are starting to like me.

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Re: Sb50p sticker bomb build

Post by Chubbyfunkmonkey » Mon Nov 06, 2017 11:44 pm

I like a challenge. The reason I'm trying to get to 35mph with the stock motor is because everyone keeps telling me I can't. I'm working on an 80s single gear 2 stroke, I know its going to be an uphill battle. Tomorrow will bring the truth and I'll accept apologies then, or maybe I'll make some apologies of my own. All I know is that all tacked together the new pipe looks and sounds great, even with the hot exhaust spraying out all seams. I'll try to get the pics up using flickr tomorrow since photobucket doesn't seem to be working. I do appreciate all the advice but if I was looking to make it go really fast I gave a 150cc gy6 and harness on my shelf. This build is about making something out of nothing for no money and so far I'm having a blast. Hopefully when I'm done I can find someone in seattle with a stock sb50p to compare it to
1989 sb50p
2005 ruckus 50cc custom
2009 ruckus 125cc 4speed

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Re: Sb50p sticker bomb build

Post by eclark5483 » Tue Nov 07, 2017 12:10 am

An SB50 does 35-40 stock, if you aren't getting even that, you have problems other then the pipe. Put the pipe back the way it was and I'll go over later when I get home from work what the trouble more then likely is. Trying to modify that pipe is only going to make the problem worse.
Indian Motorcycle tech @ Polaris Industries, B.A. Information Technology, A.A. Engineering
3 Sprees
1 ATM50-A1
1 Indian AMI-50
World's Greatest Spree: https://www.youtube.com/watch?v=lU49lL_Xx4s
Want to make a Spree engine go fast? CLICK HERE: LINK

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