Fix or Swap? Need help & input!

slosquirrel · Post by **slosquirrel** » Mon May 05, 2008 7:12 pm

I recently bought a 1989 SB50 Elite, it has 1,200 miles on it and was a good deal. It has served its purpose so far, but broke the other day. I haven't had the time to dig into it yet, so I'm not exactly sure what happened. But I'm sure it's not good.
The electric starter was working intermittently, so I was using the kick starter. On one kick the start lever didn't return, and I had to retract it manually. It did this a few times until the last, when, after returning the kick start manually it seized up and wouldn't let me kick it over at all.
Like I said I'm not exactly sure how bad it's gonna be, but the question is where do I call it quits on this engine? It was dog slow from the beginning (extremely slow on take off, couldn't pull me up hills, slow top speed, etc.) and from what I've read there aren't any modifications available for this engine.
What motors would bolt on with relative ease, have power, reliability, and not completely break the bank? Would an SA50 off of a 94+ Elite fit the bill? What modifications would have to be done to make it work?
Any help would be greatly appreciated... PLEASE!!!

mopedman · Post by **mopedman** » Tue May 06, 2008 11:31 pm

well it doesn't just bolt up. but u can fix the one you got now take the kick start cover off it could just be the kick start gears

Post by **noiseguy** » Wed May 07, 2008 12:45 pm

Anything with a variator (87-93 or 94+ Elite) would be better than stock SB50.

Your compression was probably shot if it was that slow; pull the head and I'm guessing there will be scoring. Rebuild vs. replace tradeoff at this point.

There are some cool parts for Spree off that engine that you can sell to offset the cost.

slosquirrel · Post by **slosquirrel** » Wed May 07, 2008 5:30 pm

So... I am a noob to this site, and scooters for the most part. But I grew up riding and working on motorcycles, so I'm not a complete moron. I currently finished up a complete rebuild/overhaul, and supermoto conversion of my 2000 CA legal Yamaha WR400 (not trying to brag, just giving you an idea of my capabilities).

What do you mean by "not an exact bolt on"? Does the electronic, oil, and fuel systems interchange? Do the cables work (brake/throttle)? Would anything have to be fabricated (brackets, etc.)? What about the pipe? Does anyone have knowledge of this swap, or could point me to a link that would help me better determine what I am getting myself into?

I am leaning towards an engine swap at this point. I want my scooter to be able to cruz at 35-40 with relative ease, and I know thats pretty much impossible with my SB50 motor.

I know that it would be easier to just purchase a different scooter (94+), but funds are limited, and I would love to get this thing up and running on my own. Any help, input, or direction would be greatly appreciated... PLEASE!!!

maddog · Post by **maddog** » Thu May 08, 2008 4:52 am

if you have to ask about an engine swap then you are better off with an elite-s its easy on the wallet and you can take your time building it up!

Post by **noiseguy** » Thu May 08, 2008 9:32 am

You'll need to fab / modify the motor mount, shock mount needs a dogbone (or otherwise changed). Electrical involves looking at both wiring diagrams and matching the wires up; the stock CDI will work. Throttle cable may require conversion from a single to 2-cable setup, unless you run an overbore kit and wire the oil pump wide open.

Otherwise the engine is self-contained from intake to exhaust so it's a "simple" swap.

slosquirrel · Post by **slosquirrel** » Thu May 08, 2008 2:54 pm

I realize that going with an elite s would be the easier option, but I'm a broke college student and don't have $1,000+ to spend. I already have the elite, it's registered, insured, in my name, and I only paid $300 for it when it was running and reliable. So I'm pretty sure that the engine swap will be the most cost effective.

That being said... Where is the best place to get an SA50 motor (94+)? What parts should I make sure are included (carb, pipe, etc...)? What would be a fair price? And if it needs a minor rebuild, how much do these usually run (just the parts). Also, regarding the oil pump, do people ever disconnect these and just run pre-mix? I have a '05 CR125 and couldn't help but wonder.

Furthermore, same ol' question. Has anyone done this? Are there any pics, links, etc. out there? I feel confident in my abilities, but don't want to get in over my head. Because even though I know 4-stroke motorcycle (thumper) engines, a 2-stroke scooter engine is quite different.

Post by **noiseguy** » Sat May 10, 2008 5:27 am

It's going to be cheaper / easier to get it running again in stock form.

tzmach1 · Post by **tzmach1** » Sat May 10, 2008 8:36 am

You may want to check the kick start first, the pinion gear rudes in the outer case half and can bind up if not lubed properly. I had it happen on one of my '86 Sprees, I could not get the kick lever to move at all, pulled the cover and pinion gear, cleaned and greased it and is now working perfectly.

eight08boy · Post by **eight08boy** » Thu May 15, 2008 1:22 am

if u can not get it working and want 2 part out let me know