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JP's Broom (CL350) Restoration

12K views 80 replies 9 participants last post by  ancientdad 
#1 · (Edited)
JP's Broom (CL350) Resto-Mod

Hey everyone, I've been lurking on this site since last summer--before I got my bike. This is my project thread.
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Long story short I got played on this bike. It was basically in "barn find" condition, but I didn't know it until after I started to ride it home...
I rode it 50 miles home from suburbs to Chicago and immediately noticed that it was not in the best condition. The PO did say that it had been sitting for about 4 months--I think it was a bit longer than that. It struggled to reach 45mph (bad carbs and timing). The both wheels wobbled; Out of true. Handlebars were bent and one of the front fender mounts on left side was broken, so it was missing the screw. Right hand side / upper muffler was covered in JBweld and rattling loose.
This is the bike the day I got it
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So, I overhauled the carbs about a week after getting the bike, adjusted timing (Thank you Common Motor Collective for the how-to vid), and I removed the JB weld from the muffler and wrapped it with ceramic muffler cast. I then started browsing this site for clues as to what else I should be replacing repairing.

Since then I have replaced the Plugs and boots, Trued my wheels, Replaced the air filters with NOS, Overhauled the Triple Tree,
Installed the Radioshack Rectifier,
I replaced the entire front fork springs/damper/sleve
Tool accessory Screw

Pulled the engine and opened the cylinders; Will be either honing or Boring to .50 size Pistons/rings
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Lapped the Valves because they were caked with soot (leaky head gasket).
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, Replaced the Swing Arm bushings with Bronze ones
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, New Euro bars n Grips
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What I plan to do next is get the cylinders to the shop and have them tell me if I can get away with honing or if I should bore. Install new points, get new battery, new mufflers.
Also, waiting on the replacement Cam chain tensioner roller set
Metal
 
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#2 ·
Excellent JP!!! I think you'll be able to make that into a great little Scrambler. I too went the route of honing first then mic-ing the pistons/jugs to see if I need to bore over or just size up the rings. I was able to use my .25 over pistons and use 2-over rings to get my engine together.
 
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#4 ·
Yes that's true if you have it bored over. It turns out on my bike that the jugs were straight and didn't need any work other than honing. When the machinist used the mic on the piston and jugs they were within tolerance and he told me I needed the 2 over rings.
 
#12 ·
while not absolutely terrible it is NOT a good idea to install rings of a different size like this

a good engine builder will tell you the same. It makes you compress the ringes more than they were intended for which leads to increased wear and more filing to get proper ring end gap
 
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#6 · (Edited)
Just ordered the .5 Over size piston kit from Scrambler Cycle. Now I wait for the pistons to arrive and I can bring the cylinders and pistons to the nearest shop that can bore and hone for me...
Here's a pic of the bike while it was running but before I realized that the engine needed to be pulled (amongst other things). I realize I should not have been riding without the front fender...
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#13 ·
I did have to file the ring ends just a bit - 10 strokes or so to get the right gap. Compression is good so it works for now. Hope I don't have any problems with it.
 
#14 · (Edited)
All's quiet on the midwestern front... I can't, for the life of me, find a motorcycle shop that does bore and honing in Chicago. That is just about all I need done so that I can reassemble the engine to move forward. SMH

Question: Will an auto repair shop do Bore and Honing if I bring my cylinder head to them? I really would prefer to find some place local.

Also, I am going .5mm up with the cylinders. Can I get away with doing this myself with a honing tool or is .5 too large for that to work?
 
#15 ·
Try and find a high performance speed shop that builds engines. Or you can try and find a small engine repair place that may be able to help you.

And don't feel bad - I had my jugs at a speed shop for 5 months before I picked them up and took them somewhere else. The new place had them done in a week. I was completely stalled on my engine build until that part was machined. Once it was done I was able to finish the engine and move on to other items. A suggestion is to get your wiring harness, rims/tires, frame and lighting sorted while you are waiting... Wish I had.
 
#16 ·
WUPF!
I went through a number of machinists, moto repair, high performance shops, etc in the past 5 days. Finally came across MCC in Villa Park Illinois. (another member had mentioned them for a bore and hone job in the midwest...
well i dropped off the jugs and new pistons to be bored out.

at the same time I received the OIL seal kit, which i went to town on... I replaced the obvious oil seals.

ill keep posting as time allows for progress.
 
#18 · (Edited)
JP I live in near Schaumburg so I would love to see pictures and know how your experience is at MCC.
Thanks!
I will upload more pix once I get the cylinders back.
As for the service/experience at MCC, it was on point thus far. My first interaction with them was through email. The person who responded is Bob "Speedy" Pirog he is the person I asked to speak with the day I went to MCC. I think I brought a bit of nostalgia to him because Bob put on a huge grin when I told him I was rebuilding a '73 CL350. He then said he used to have a 73 CL360. Service area is organized and clean. I was in and out of there in 15mins. I feel like I found the right place for the job I needed done.
Plus there's plenty of shiny bikes to oogle at...Norton Commando 961 Cafe :shock:

Anyway, here's the contact info
Bob "Speedy" Pirog
Service Manager
MCC Motor Cycle Center
443 E. St. Charles Rd.
Villa Park, IL. 60181
630.782.2015
mccservicemanager@gmail.com
 
#19 ·
Awesome thanks for the details!

I've run into quite a few bike shops that don't want to mess with such old stuff. "Takes too much time" is the response I've gotten. I'm like "who are YOU telling!" [emoji3]


Sent from my iPhone using Tapatalk
 
#20 ·
Back On track

I got the bored cylinders and new pistons/rings installed. I had a laborious Friday...
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I went full McGruber with this DIY Piston Ring Compressor thing. I did not have the money or the time to run to autozone to find the wrong piston ring compressor tool. So I made two from what i had laying around in the garage. It worked!
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Once I got to the top, made sure that everything was in line. Horizontal line on cam sprocket, lined up with the time advance pin at 12 O'clock, which lined up with the LT mark on the stator. Then I proceeded to adjust the valves.
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I also replaced the oil seals on the drive shaft, the Gear shifter shaft, and the clutch shaft. I was able to do all three without removing the right side case cover. Not sure if you need to pull the right side case cover to install the new oil seals...I just used a flat head and pried them out. Being careful not to damage anything.
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I Finished putting the engine together pretty quickly that I had time to mount the engine into the frame.
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Mounting the engine went suspiciously smooth. I did this by myself with the help of a car jack and a piece of wood between the engine and jack. Everything fit nicely.

I then kicked the engine a few times as that was recommended by many other posters on here and on youtube. I guess it helps the new rings seat nicely on the honed walls. While I was at it, I decided to check the compression and I was getting 145psi on both cylinders. I think those numbers will go up once I can get the engine at normal operating temp.
 
#21 ·
Wow! That was a quick engine build. Nice work.
 
#23 ·
Thanks Fellas

Today I plan on spending a few hours getting the rest of the bike back together and adjusting the timing. I also have a set of rear shocks off of a CB750 that I hope show up this morning. If everything goes smoothly, I hope to get the engine started by Sunday.

-Steve
The cylinders and hone were done nicely by MCC they even got the ring gap spacing correct. I would highly recommend MCC to anyone. I ended up paying 200 for the bore and hone.
 
#24 · (Edited)
I just received the CB750 rear shocks. They look to be in near mint condition. I was surprised that they were actually shorter (by about an inch and a quarter) than the CL350 shocks. I kept reading that the CB750 shocks would be taller than the CL shocks. Weird. In any case, for those who want to drop the rear of their CL350's and increase the rigidity, I would recommend the CB750 shocks. They were bolt on right out of the box. Same hardware as CL shocks.
Why I opted for these shocks? The CL shocks were done. They were more than likely getting dry on the inside since every ride meant oil drips from the shocks. Also, Since I plan to take my partner out on weekend rides around Chicago, these shocks should help with the added weight.

What do you all think? will I run into any potential problems with these shocks? I can see going off road being a problem since the bike is dropped about an inch and 1/4...however, you don't see too many trails in Chicago.

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#25 ·
I just installed new Daiichi points and set the timing. It took me about 5hrs because i had to run around looking for replacement bolts for the points.
Afterwards i wanted to check that I was getting a spark through the spark plugs and realized that my starter is not grounded to the new handlebars. That took a few more hours of head scratching and testing wires... Why did I get black handlebars??

Does anyone know if I can run a ground wire from the triple tree to the controls housing? This is to avoid sanding the paint off the handlebars to complete the ground.
 
#26 ·
A ground is a ground...I frequently powdercoat my handlebars then sand them back to metal under the switch pods.

doesn't matter how you ground them so long as they are grounded.

if you don't want to sand, next best is adding a ground wire to the harness that runs through the bars, then find a convenient place to attach inside the switch pods...like a small ring terminal on one of the retaining screws inside or soldering to one of the retaining plates.
 
#29 · (Edited)
So, since my last update I realized that the battery was not charging through the system. I checked the stator; all readings were within spec. including output ACV readings while running the engine. I removed the Radioshack rectifier to test it; everything checked out with that too.
with everything installed I checked the battery terminals.
@Idle: 12.47v
@ Idle with lights on: 11.3v and dropping
@3000 rpm: 11.46v or less. WTF? Something is def. wrong.
I removed the battery and brought it indoors to charge; It stopped charging at 13v. When I disconnected the battery it started dropping in Volts immediately. Still off of the charger and 24hrs later it was at 12.49v, every 4hrs it would drop a volt.
I sanded the contacts on the rectifier and the battery. Installed battery (battery was at 12.47v) and rectifier. Battery then read 12.76v without the bike on...weird?

Ran the bike and here are the readings:
@idle no lights: 12.74v
@3000 rpm: 13.2

Then w/headlight & brake light, and turn signal:
@idle: 12.20v & dropping abt 6v every time turn signal went on.
@3000 rpm 12.60v fluctuating because of the turn signal but still charging.

It seems that the contacts were the culprit. I'm getting charge to the battery now!
Now what to do with the Regulator/Rectifier that I ordered a few days ago...smh.

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EDIT: I posted the following in the Cheap Regulator / Rectifier Thread
*Posting this here for my records*

Here is what I did after I confirmed that the charging system was working.

Ok peeps. Just want to report about mounting the 8amp 200v Rect. unit listed above.
I originally had it mounted behind the battery on one of the original mounting arms for the oem unit. The little unit was getting hot and I felt that it was not getting enough air to cool it off. I had it mounted on a L shaped aluminum bracket.

I decided to move the unit to sit lower and just to the left of the battery. I drilled holes in the bracket to make up for no cooling fins. The unit now only gets about as warm as 75F.

View attachment 81048 View attachment 81049

*Edit* The unit is mounted using one of the side cover mounting holes. I put a bolt through there without causing damage to the mounting hole.
 
#33 ·
I removed the battery and brought it indoors to charge; It stopped charging at 13v. When I disconnected the battery it started dropping in Volts immediately. Still off of the charger and 24hrs later it was at 12.49v, every 4hrs it would drop a volt.
This is normal battery behavior, they have a certain voltage that they want to equalize at. They will do the reverse if they are under voltage. Meaning if you wear a 12v battery down to 6v in a very short amount of time and then check it 24 hours later it will be at 8 or 9v. The battery didn't really charge itself back up it is based on the chemical reaction in the cells. The gist of it is that the chemical reactions are stablizing.

I sanded the contacts on the rectifier and the battery. Installed battery (battery was at 12.47v) and rectifier. Battery then read 12.76v without the bike on...weird?
Again, this isn't that weird to see small fluctuations. My guess is that when installing the battery it was moved around and thus more chemical stabilizing happened.

Then w/headlight & brake light, and turn signal:
@idle: 12.20v & dropping abt 6v every time turn signal went on.
@3000 rpm 12.60v fluctuating because of the turn signal but still charging.
The battery is dumping about 7-10amps of current when headlight, taillight, and turn signal is on. This is a LARGE amount of current for this tiny batteries so the battery dropping to 6v is okay. The battery should recover to close to the original voltage if it is a good battery. If it stays at 6v then you might have an undercharged or bad battery. I wouldn't recommend performing this test a lot because you are shortening the battery life.

One last point, the electric starter takes a TON of juice from the battery, about 8 amps. So extended turn overs, like you show in the video are sure to wear out your battery or drain it completely. When I'm trying to get the bike going I use the kickstarter. If tuned properly it should start within 1-3 kicks. When I'm trying to diagnose a problem I'll use a car battery because it has WAY more life in it than the motorcycle battery. BE SURE WHEN JUMPING TO HAVE THE CAR OFF. The regulator on the bike might blow out otherwise.

Great to see the working video!!!! (Nice Mad Max reference)
 
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