Recently bought 1982 Urban express Nu50, it will start on the first kick, it will idle but unable to rev much higher (barely spins the wheel). Realized that the muffler flange was not sitting flush (or tight for that matter) against the engine exhaust port when I noticed some oil dripping from there. What could be my problem? Wondering if I should bypass the oil pump and premix my own gas. Any tips would be great, would like to get this running.
1. Manual
https://drive.google.com/folderview?id=1vxdUocvohov-VU1KVuOY-9YquFpw7fok
2. Tighten up that exhaust.
3. Check your throttle cable. Is it loose? While on kickstand your rear wheel should be moving.
4. Even if it does start it, go back through maintenance section of manual and clean carb etc. It will need it if it hasn't been done. You'll need the practice anyway.
5. If this is a stock bike I'd leave the injector though a lot of people pull them. Get it running before you make changes to it.
6. Get a compression tester and see what's up. It should be over 100 to get a good start. You can get one for about $25 or see if you can borrow from AutoZone or the like.
Good luck.
So an update on my end. Got it running and tops out at 23-24 mph. I'm guessing that I can get a bit more speed by messing with the Idle screw and float screw?
It was a clogged muffler that was the culprit for my poor power. To unclog the muffler I boiled it in a big lobster pot full of Purple Power Degreaser. I did this for about 2 hours (until the degreaser ended up eating a hole through the lobster pot). Every 30 mins or so I dumped more of the Purple Power down into the muffler as well to make sure there was plenty working on the insides. I got this idea from a patient of mine (who is a mechanic). He shied away from the idea of putting the muffler straight into a burning fire, explaining how that will cause microtrauma to the inside of the muffler which would eventually result in rust formation from the inside out. I would highly recommend this to all attempting to unclog mufflers or remove carbon from engine parts.
> Kyle Gerber Wrote:
> -------------------------------------------------------
> So an update on my end. Got it running and tops out at 23-24 mph. I'm
> guessing that I can get a bit more speed by messing with the Idle screw
> and float screw?
>
> It was a clogged muffler that was the culprit for my poor power. To
> unclog the muffler I boiled it in a big lobster pot full of Purple Power
> Degreaser. I did this for about 2 hours (until the degreaser ended up
> eating a hole through the lobster pot). Every 30 mins or so I dumped
> more of the Purple Power down into the muffler as well to make sure
> there was plenty working on the insides. I got this idea from a patient
> of mine (who is a mechanic). He shied away from the idea of putting the
> muffler straight into a burning fire, explaining how that will cause
> microtrauma to the inside of the muffler which would eventually result
> in rust formation from the inside out. I would highly recommend this to
> all attempting to unclog mufflers or remove carbon from engine parts.
That seems a huge over kill , when a dollars worth of oven cleaner or drain opener will do as good or better and not cost you a lobster pot . LOL
Agreed on the direct fire route . I never thought that to be a very good idea .
I have put a fair amount of gas into a muffler and lit it . Had pretty good results from that , but , oven cleaner or drain opener is much safer, cheaper and quicker . (edited)
most Urbans are jetted too rich with the stock carb. My guess would be that you try a smaller main jet to get a couple few more mphs out of it. You can try to lean out the air screw but main jet is where it's at.
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