Bobber Build by a total Newb

Great job dilbone!:thumbsup: I know what your talking about with the noises.:laugh: I'm just getting to where I'm relaxing on mine! Still think at times this thing could fallout from underneath me at anytime!:eek: Yeah, rethink the rear fender man, you'll want something to keep your ass from being burned off when you slide off of the seat.:wink2:
I dig the clean look of your handle bar setup.
 
No Problem Fellas

Johnt3 said:
Great job dilbone!:thumbsup: I know what your talking about with the noises.:laugh: I'm just getting to where I'm relaxing on mine! Still think at times this thing could fallout from underneath me at anytime!:eek: Yeah, rethink the rear fender man, you'll want something to keep your ass from being burned off when you slide off of the seat.:wink2:
I dig the clean look of your handle bar setup.
Click to expand...


Thanks John. I've been pretty impressed so far with how comfortable this bike is with the 4" springs. Bumps hardly seem noticeable...the bike gets jarred, but my but and back feel pretty good so far...waaaaaaay better than I expected. But yeah, I need to work on a rear fender...
 
Well for my own peace of mind I decided to use a nylon spacer as a guard for the electronics tank above the chain. It definitely had chain contact while riding today...but the tank is fine...looks like I'll probably need a tensioner pulley on this. At least I'm not worried about tearing anything up now.
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I stole an idea from someone on here about baffles. I've made baffles before but it involved automotive exhaust adapters, welding, and drilling holes. I saw this one using electrical conduit and had to try it.
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I shoved them in the ends of the header pipes and they definitely take some of the high end edge off of the volume and it just sounds/feels better IMO. I may take them out again tomorrow and wrap a small bit of fiberglass around the center section to block the flow just a bit more.

Here are a couple of videos one without the baffles and one with. It didn't really get quieter but the high frequency shrill tone got toned down for sure. I think it sounds better...and I can actually hear the engine when riding it now.

without baffles

with baffles
 
I'm glad to hear that your bike rides out good dilbone. I went with the 3" springs on mine and they seem to work okay, but the ride is still pretty rough at times though. I'll being installing a new rear tire and that might help soften it up a little. I think the tire that's on there now has got to be damn near 30 years old!:D It's hard as a rock.
 
I was messing around with the carbs last night and made things way worse before they got better. My left cylinder was rock steady with a nice pop at equal time intervals...the right not so much. It was very erratic and every once in a while had a loud pop as well. I noticed after not too much running time the left baffle was covered in soot while the right looked like it did when I put it in and the right side exhaust temperature seemed very cool compared to the very hot left side.

I started at this point to mess with the sync screw. I started to back it out and the popping got worse and a crack of the throttle and it didn't like it one bit. I then started to take it in a quarter turn at a time and it got better. The more I took it in the idle would start to climb and I would then back out the idle screw back down to 1200rpm. I did that a few times and finally got what was a much steadier rap from the right side and the temp of the exhaust was definitely going up and beginning to match the left side.

The throttle response after this was much better and the whole bike seemed to settle and run much smoother. I took it out around the country block and it ran sooooo much smoother than it had been. Also I noticed when I got back that the seat pan was hardly moving at all while the bike idled...before that seat was bouncing up and down like a jack hammer. I don't know if it was just a resonance frequency thing between the motor and the springs but things definitely changed for the better.

I noticed the right side vacuum port on the intake is actually plugged so I'm going to have to probably pop off the carbs and clean that out before I try to do a sync with my manometer setup.
 
Johnt3 said:
I'm glad to hear that your bike rides out good dilbone. I went with the 3" springs on mine and they seem to work okay, but the ride is still pretty rough at times though. I'll being installing a new rear tire and that might help soften it up a little. I think the tire that's on there now has got to be damn near 30 years old!:D It's hard as a rock.
Click to expand...

Yeah, my rear tire is in horrible shape...well both of them really, like you said, hard as a rock. The tubes are actually holding air quite well though I must say, but tires are definitely on the sooner than later list for me. I was looking at the schinko classic 240 for the rear and an avon speedmaster front.
 
Yeah that does look good Carbon. I can't see me doing many twisties on this thing...the kickstand would get ripped off if I did. By the way, I really hope your recovery is going well. I haven't posted about it in your thread, but I've checked in and hope the healing goes faster than expected.

Also, I love your electronics box...that access panel turned out awesome.
 
thanks Man.
I will be taking twisties slow on my XS as well.
the shoulder is coming along good.
better than I thought :thumbsup:.
Your baby sounds good with the baffels :thumbsup:thats what I'm talking about!
ride safe Brother!
 
three lessons learned tonight:

1. make sure to cover the blinker relay with electrical tape so it can't make contact with the ground and the positive post of the fuse block

2. make sure to throw a spare 10A and 20A fuse in the tank

3. make sure to carry an 1/8" allen wrench to open the tank


don't ask me how I learned these...:doh:...:bike:
 
Dilbone, did you cut your header and how did you secure it to the frame. I have to cut my headers cause they won't clear my brake pedal if i mount them to the stock mount. I'm planning on baffles as well as it will probably be pretty raw.
 
hard_y_rd said:
Dilbone, did you cut your header and how did you secure it to the frame. I have to cut my headers cause they won't clear my brake pedal if i mount them to the stock mount. I'm planning on baffles as well as it will probably be pretty raw.
Click to expand...

Yes I cut the header just in front of the hanger tab since my pegs use the old exhaust mount holes they were never going to fit. It isn't secured to the frame, I don't think they're long enough to have to worry about bolting to the frame.
I could be wrong on that but they don't seem to be causing a problem yet.
I doubt I will stay with the stock headers in the long run. I'll probably buy some from Gordon Scott...he's got some really cool looking pipes, but that might be one of the last things I do when cash becomes available. For now the stock will work.

Baffles are a good idea...definitely takes the shrill edge off
 
Today I set out to sync the carbs. I felt like I got them pretty close the other day just by listening to the exhausts, but I wanted to verify with the manometer. I had previously made one for an old '75 CB550 I had, so I had to unhook two branches and plug them off so I could use it again.

They ended up being VERY close already with only a couple of tweaks on the sync screw to bring them into balance. That rattle in the video is actually the seat pan jack hammering up and down at idle...apparently I must have hit the right frequency to send it into resonance again...


Then I decided to try the "dead cylinder" method of mixture screw adjustment using the vacuum ports on the intakes to disable one side at a time. Here's where it got weird...the left carb had the highest idle with the mixture screw barely cracked open. The right carb was open about 5 turns when it reached max idle...
I decided to screw it...no punn intened...and set them both at 3 turns out(they had been 2.5 turns at this point and I was getting a fair amount of exhaust pop).
What do ya know, all of the popping on deceleration is gone now and this bike runs like a little 650cc beast. I had it up past 75 today and it had plenty left, but on these old cracked tires I'm not going to do that again.

I have a rattle in the right exhaust I've noticed. The inner pipe is rattling inside the outer...I need to shove something in between them to dampen it. Otherwise I'm pretty pleased with how it ran today...Rock steady idle, much smoother than it's been, and no deceleration pop...

I still need to take a closer look at the cam chain tension. I took the acorn nut off and spun the motor a few times with the kicker. I think it looked like it had more than the 1-2mm of movement from the pin. I think I'll take the acorn off while it's idling and see what it looks like...then pick up a 27mm deep well socket to adjust if need be.
 
Woe, Woe you better slow down dilbone!:wink2: I'm a pussy for only doing 60 on my old hard rear tire!:D
I'm going with the Pirelli MT66-Route for mine, I like the look and it has decent ratings.
I'm glad you got your carbs synced, sounds good man.:bike:
 
HaHa!!!!

I gotta get new rubber on this...it's begging to go faster!!!!!!!!

You know, those pirelli's look pretty good and even cheaper than my picks. I don't mind the tread pattern either for a more modern tire. Now you got me thinking...
 
Hey Dilbone great build man I gotta say you don't look like a newb from going over yer thread i'd say you really know what yer doing i on the other hand am a newb and don't have a clue what i got myself into lol i just started a build and it will be slow for i don't have the money or much time but i will be learning from yer thread as i go all i have done is hardtail the frame and powdercoat my wheels and stare at all the motor parts in my basket trying to figure out where to start putting this thing back together.
 

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