1st post on any forum ever...83 xs 400 maxim

[GentleGiantATX]

Hey there y'all! Super stoked to have been able to acquire this 1983 XS400 Maxim for free but it was a long journey to get it to even start which is why it was free. Best part was that it came with a bucket of random bolts and parts that I had to guess what went where and how to hand torque everything from coils and plugs to sprocket and brakes. Had to clean the jets and bench sync everything 9 times before I got to where I am now and still working out a few kinks but damn these things are fun! Air box is really tricky to connect to the carbs as the boots are stiff and cracking and I choke it on the carb to start but only because I have to disconnect the vacuum hose after I get it warmed up or the rpm is hard to get leveled out with it on. I know I have some work to do yet but for the moment it runs like a raped ape and really shits n gits with a clutch dump in 1st gear at about 20mph redlining at 10,500 rpm and pumping 2nd through 5th at 7,500 rpm!! Kinda sketchy but so far I've been able to pull 127mph before I let off just because I'm 6 foot 10 and the bike gets squirrelly in the front tire I guess because I am like a big wind catch or something but never had I expected a 400cc vintage bike to be a ripper lol. I've been able to outrun a cbr600rr so far from a dig and I suppose the 3 foot flame might have scared the cbr rider and caused him to back down but the exhaust is harmonic and beautiful when I twist the throttle so that alone makes it all worthwhile. Cut mufflers right behind passenger pegs btw and fabricating my own baffles currently but till they're done it's wide open sounds of freedom and fun.

 

[OMeGA_65]

You've done a great job

 

[GuyS]

Nice bike. Free? Lucky you. I’m totally redoing a 1982 Maxim 400 but haven’t got to the starting it, for what will be the first time in years. I’ve found the Maxim quite abit different from the “normal” XS 400’s. I’ll be more than happy to share my experience in mechanically restoring mine.

 

[GentleGiantATX]

Well it was running great and the only thing I can think is that the bike is settling into its norm of things and the carbs will need to be cleaned every 15th or 20th tank of gas cause now it is lugging one cylinder while I'm on the interstate running constant 6k-8k rpm. I usually stay away from I 35 because I know it will go fast enough but not for very long. Took plugs out and they saying I'm lean n one prong was completely melted to the little diode thing so I replaced it and it started up and ran fine. I'm not a motorcycle mechanic at all but I'm not mechanically challenged either so I can usually find the problem and re engineer it to work slightly better or as good as OEM it's just the parts origin that freaks people out like the in line fuel filter is from a riding mower and the exhaust is custom baffles that I made from trampoline pipes and the throttle cable is a bicycle gear selection cable lol I'm kinda surprised it works as well as it does and always surprising to feel the sheer amount of power it has or how smoothly it corners...I'm rambling now so I'll end this here and hope to find riders of vintage bikes in Austin soon

 

[XSSmith]

Dude, that XS400 sounds like a total beast! Free bike, bucket of bolts, and 127mph? You're livin' the dream! Keep wrenchin' and enjoy the ride man!