Thanks for the info Chris, I would not of known to check that. If I have any issues I will definately order new ones from Jetsareus.com Can you give me a rough estimate of jet size for pod filters and aftermarket exhaust. I will need a set for both Florida and Colorado. The elevation change will be 10,000 ft. The town I live in is 7,300 above sea level. I was thinking 137.5 for Florida , which is two sizes over stock. Does that sound right?
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1980xs Brat Project
- Thread starter Noah
- Start date
No idea on jets as every bike is different. Stock mains are 135. I would highly recommend getting the stock H-pipe for the intake and putting some black foam uni filters on it. 6" full foam. This will also allow you to hook up the crank case breather hose. It will help with tuning greatly. A good muffler that has actual baffles will also help. There are lots of things to look at for jetting not just the mains. You need to address pilot jets, pilot mix screws, needle jet positions and even float height. This is why after 21 years of riding these bike and trying and using all different air filter and muffler setups I use fully stock only. You can get them to run ok with non stock stuff but to make them have the best overall performance stock works better. I have put bikes together that where total crap heaps and being able to tune them in minutes. Yamaha had them mostly right from the factory. The only settings I need to change is the pilot mix screws going from 1.5 turns out to 3.
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Specdog
XS400 Addict
Measure your axle, it may just fit.
Not sure what you are referencing Specdog,
I found out after more research this is one off those wacky attempts to reinvent the wheel of this bike. Called PMA or Permanent Magnet Alternator.. Not sure I'm on board. I feel the stock charging system would have been more than adequate for this bike.
I found out after more research this is one off those wacky attempts to reinvent the wheel of this bike. Called PMA or Permanent Magnet Alternator.. Not sure I'm on board. I feel the stock charging system would have been more than adequate for this bike.
Specdog
XS400 Addict
Sometimes the thread of the axle will match the rotor threads and can be used to pull the rotor.
Specdog
XS400 Addict
I just checked, the XS400 axle is 13mm. The stock rotor is 16mm with a 1.5 pitch. Check if your aftermarket rotor is 13mm
Thank you for the help and advice, I was able to remove the flywheel using a bolt behind the puller. Here's a pic, got the original flywheel and starter system hooked back up, on to the next step... Rewiring with the factory harness I have and rejetting the carbs. Then front caliper and hopefully a test ride.
Update*
Having trouble getting the motor to pop using the factory harness. Appears to be all hooked up correctly. My question is this starter solenoid. Is there a way to bypass it? I'm thinking it may be my culprit.
Update*
Having trouble getting the motor to pop using the factory harness. Appears to be all hooked up correctly. My question is this starter solenoid. Is there a way to bypass it? I'm thinking it may be my culprit.
Attachments
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Thanks Cafe! I am currently stuck at the rewiring phase. I completely removed the hacked wiring that was on the 1980 that I am working on and used the factory harness from the 1981 parts bike. I haven't been able to get spark now. In assuming the wiring harness will be compatible despite the minor changes during 80-81? Also will any of the xs400 s or sh wiring diagrams work? I am planning to find one of the better simplified harnesses that are posted in various threads on this site to backtrack through the factory harness and remove all unnecessary wiring. I'm sure its something simple, the bike did run before. I'm thinking its probably something with the ignition or starter solenoid/relay. ....When I had it hooked up last to test, I was using a questionable battery. Would it need the full 12v from battery to see spark at plug electrode?
Update
I got the wiring figured out and got her to run with the new jets. Every thing seemed all good until the next day. Battery was dead. Guess I have a short/ground issue or just a bad battery. Since its kick start only right now, I am looking for the smallest battery possible. I saw xschris runs a 1.3 ah he found or 9$, I'm looking for one that is small and cheap like that. Would this one work?https://www.batteriesplus.com/produ...je_bDi94nUpc9P8IjCbzO2LhroiCZvvQaAkL0EALw_wcB
I got the wiring figured out and got her to run with the new jets. Every thing seemed all good until the next day. Battery was dead. Guess I have a short/ground issue or just a bad battery. Since its kick start only right now, I am looking for the smallest battery possible. I saw xschris runs a 1.3 ah he found or 9$, I'm looking for one that is small and cheap like that. Would this one work?https://www.batteriesplus.com/produ...je_bDi94nUpc9P8IjCbzO2LhroiCZvvQaAkL0EALw_wcB
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You have to see what the max charge for the battery is. It has to be able to handle at least 14.5-14.7v. The one I used was rated to 15v. I would get a larger AH battery if I was you. Your bike needs to be able to start on the first kick and have little light bulb draw. These little batteries will get wiped very fast. I went back to fully stock battery and e-start after a few years as my back don't like the kicking. They do make small light batteries that can e-start a bike still but cost lots of money.
I decided to use a stock size battery, got the starter hooked up and fabbed up a battery box, there wasn't too many options on where to put it. I'm one step closer. Next is headlight/tailight and swap gas tanks( I've been soaking it in white vinegar, looking for a new petcock at the moment.
