'82 Bar Hopper

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This thread will outline my modifications to the last of my Dad's XS650s. This bike is an 1982 which has had some fairly substantial frame modifications. Dad built this bike approximately 10 years ago, but never rode it much. He always referred to it as a "bar hopper" which I believe is because it was somewhat unreliable. Dad always enjoyed building them much more than riding.

Here is the bike as it stands today:
upload_2021-6-20_11-21-37.png


The original plan was for this to be my first project bike, so I have no qualms with modifying it as I see fit. The first step was to address the rusty tank and carbs. Good thing I have recently had some recent experience with this!

I first did a slosh with some screws and acetone to eat away at some of the varnish. From here, I rinsed and let some Evaporust sit for a day or so. That stuff works great! The seams looked pretty rough, so I decided to use a POR15 kit that I had laying around. This whole process took most all of a weekend, but it turned out really well.

upload_2021-6-20_11-14-6.png


From here is was onto the VM34s. This is my first time messing with this style of carb and I found them to be very easy to work with. I disassembled them and got out all the nasty rotten gas with a carb dip. From here I blew out all of the passages and looked at my jetting. I found a great guide that helped me with this. The carbs had a 159-P6 needle jet, a 6F9 needle, #15 pilot, and a #175 main jet. From the guide, I decided to try and increase the pilot to a #22.5 and the main to a #190. I took out the air jet all together.

upload_2021-6-20_11-19-56.jpeg


Got these all mounted up and will soon begin tuning. I am going to let the POR15 cure out for a good long time before I add any ethanol-free gas to it.
upload_2021-6-20_11-22-36.png


Looking down the road, I'm not totally sure what else I am going to do to this bike. I am a little excited about not having to stay true to any factory specification. If I remember correctly, the engine has a 750 kit in it and I think he did a cam and valves, too. I have been wanting to try and re-phase an engine... It is also in need of some new paint. The electrics could be cleaned up quite a bit, as well. Stay tuned!
 
Looking down the road, I'm not totally sure what else I am going to do to this bike. I am a little excited about not having to stay true to any factory specification. If I remember correctly, the engine has a 750 kit in it and I think he did a cam and valves, too. I have been wanting to try and re-phase an engine... It is also in need of some new paint. The electrics could be cleaned up quite a bit, as well. Stay tuned

:popcorn::popcorn::popcorn:
 
Well, I think they're going to stick out no matter what, but hopefully the angled version won't jam into the frame like that and bend the filter.
 
I have a couple of questions about these carbs that I have not been able to find a satisfactory answer for. Mainly, what is the best practice for routing the vent lines from the VM34s? I understand the lower hose from the bowl is something like a gas overflow, so I imagine it should aim somewhere it is (relatively) safe to leak gasoline. What about the other hose? Does it need to be connected to vacuum? Speaking of vacuum, where would I connect my manometer to sync the carbs?
 
Both are open to atmosphere. Though an argument might be made to the advantages of routing the top hose inside the air filter AFAIK this is seldom if ever done.
 

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