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Discussion Starter #21
The left carburetor was a different story... installed on the bike I squeezed onto the petrified plastic fuel line and gave a tug to remove it off the stand pipe... no go.. so then using a twisting action and pulling... yup you guessed it.. I removed the standpipe haha... will have to fix that (lesson learned). The photo shows the line installed, but you can see where I grabbed the plastic line... will use a razor blade next time :)

I noticed the choke linkage was backed off. When I flipped the choke lever there was no choke appearing in view.. only the pin that would attach to the choke valve came into view... hmmm that loose linkage me had think the choke valve had released (or was removed by the PO)... if it released its next stop would be the intake valve. The floats were damaged. The fuel bowl area was not as nice as the right side carburetor.
 

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Discussion Starter #22
It was time to remove the engine from the frame. I lowered the bike on its side with the engine being supported by some pads I use when crawling under cars. It looked like this would make it easy to remove the engine by one person. It was.

I was about to start releasing the frame/engine mount bolts I noticed the oil drain plug had what looked like some sort of pink putty around the base. I unscrewed the oil drain plug, for a closer look and this was found laying in the bottom of the plug. At first, thought it was a gear tooth... but nope (wrong radii), it's a broken off finger/tab from the magneto-rotor. If you recall the cracked ones I showed earlier, this is one that was broken off and laying in the engine :/ I haven't determined was that pink stuff was, but I am replacing the plug from previous PO damage in their attempt to remove it.
 

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Discussion Starter #25 (Edited)
Pink gunkay well be a home made gasket, that stuff kills these motors
Absolutley !!

I forgot to mention after I removed the goo from the spark plugs, the left spark plug had "zero" gap clearance, and the right one had .002" ahhahahhah

Here is a picture I took this morning of the rotor looking at it with the three staked screws holding the starter mechanism removed (they were very tight, as they should have been), for a little closer at the tabs/fingers... you can see the missing tab/finger (... the broken off piece fits perfectly in its place). Turns out the remaining five tabs are cracked. Cruising Ebay etc, everything I viewed that was in "used condition" appear to have cracked tabs/fingers. There is one NOS out there but will leave that for the folks who fully restore and sell. I have been reviewing alternatives for about a month or so.
 

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Discussion Starter #26 (Edited)
Some of the alternatives I've reviewed for supplying higher than stock watt output, included:

- Powerdynamo for Honda CB175
This appears to use a field controlled alternator and adds an electronic crankshaft sensor for ignition timing. It has about a 150w output; looking similar to a Honda 400F / 500F electrical power system.. dunno.. the down side is the electric start has to be removed. Kick start lovers might be interested in something like this.. not for me though. The cost appears to be a tad higher than a Bore Tech ignition system, but might be worth it for some folks.

- Amazon.com: DB Electrical APM0008 Alternator for John Deere Utility Tractor for Models 670, 770, 790, 870, 970, 990, 1070 and 2305: Automotive
This is a 3 phase (IIRC 300w) permanent magnetic alternator... down side is the excess power is being absorbed (wasted). This has been used as a back-up electrical source with experimental aircraft builders with good success. I have no idea what the break-in voltage rpm or rotating rpm limitations are. There is a two wire (single phase) version of this also. This link will show a typical installation on an experimental aircraft using a corvair engine... http://www.n56ml.com/corvair/dynamo.html

Am still looking at other alternatives.. no rush for me :) If there's other possible/viable options/alternatives your aware of.. yell!
 

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Discussion Starter #27 (Edited)
Engine dis-assembly

NOTE: When the frame was upside down with the engine installed, I was able to break free all but three case half bolts on the lower case... the other three were blocked by the frame. With the frame bracing the engine, this was easily accomplished.

Removed the cam chain, cam bosses and cam. These are in great shape.. no oil starvation observed... this was a good thing. Then removed the cylinder head and cylinder assemblies.

The right hand piston skirt was badly scrapped below the oil scavenger rings. The piston was tilted over to one side. This was caused by either something getting caught between the bottom of the skirt, or the PO had this apart and banged the skirt (hard) into the upper case, as the bottom of the skirt was cracked and dented in such a way that forced the piston to tilt over in the cylinder liner... I think it was the latter. The inward dent/crack is easy to see in the photo, but the corners of the dented/cracked area is pushed outward... hard to see. With the piston rings removed, the piston was difficult to put back into the cylinder (because of the outward bends). Liner scrapes are easily felt by fingernail. Ouchie !
 

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Discussion Starter #28 (Edited)
The left piston crown (top) looked like an itty bitty ball peen taken to it. The combustion chamber was badly cut, gouged etc.. yup me thinks this is where the missing choke valve assembly visited.

NOTE: The combustion chamber was full of goo from the previous pre-soak, and I did not immediatley notice the outer part of the choke valve was wedged into the combustion chamber and the damage that it caused. A week or so later I was showing my youngest son and his wife where I was with the project. My daughter-in-law actually spotted the choke valve assembly stuck in the combustion chamber, and she knew exactly what it was.. she grew up rebuilding small motorcycles with her dad.

The center section (flap valve) of the choke valve was not found in the combustion chamber, but there is a noisy rattle when I shake the left exhaust pipe around.

PS: Sry ..I did not take any pictures when combustion chamber damaged area, only when I repaired it.. will post that later in the log :)

Cheers
 

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You could expand your rotor search to include any of the model variance ca,cb,cl,cd etc 175's and cb/cl200's. You'll need to get maching advancers or possibly remark the rotor as the timing marks shift through models. If you look for a used model that was kicker only (sl ,some cl, some ca,some cd) they will have the tabs but they won't have the stress cranks
 

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Discussion Starter #30
You could expand your rotor search to include any of the model variance ca,cb,cl,cd etc 175's and cb/cl200's. You'll need to get maching advancers or possibly remark the rotor as the timing marks shift through models. If you look for a used model that was kicker only (sl ,some cl, some ca,some cd) they will have the tabs but they won't have the stress cranks
I did not think of the kicker bikes .. furthest thing from my mind... will look around .. Thanks!
 

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Discussion Starter #32
Also the cb/cl 200 stator is a bolt on 7watt upgrade and a 350 stator can be made to fit (with a drill and adding a timing market) if you need even more juice
Thanks Simo, !

Cheers
 

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Discussion Starter #33

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Discussion Starter #34 (Edited)
The cylinder liners and pistons will be upgraded. This requires a few modifications to the replacement cylinder liners and upper engine case to fit the donor liners in.

The slipper pistons are 57mm w/14mm wrist pins. They are from Tbolt and inspired by Triumpsuper3's (Patrick's) Lucky & Zeke builds.
.TB 824 PISTON 57mm x 14mm pin - Pit Bike Engine Parts - Piston Kits - TBW0824 - TBolt USA, LLC

A CB500 Four cylinder assembly was found locally ($20 usd). The standard bore is 56mm. This allows the fit of the Tbolt 57mm piston to the max oversize allowed (57mm) for the cylinder. The upper liner lip thickness and length of the liner will be machined to initially match the CB175 liner. Because of the height difference between the CB175 piston and the Tbolt piston, I might shorten the donor liner further... dunno yet. Other mods may be required.

Pictures show the liner/piston comparison, and, of the CB500 Four liners as received and one honed out with a wiper blade... needed to check/confirm the initial bore. :)

Cheers
 

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Discussion Starter #36 (Edited)
Are the 500/4 liners the same OD as the 175 or are you also boring the cases
Hi Simo :) Short answer .... I have to bore the upper case housing. The liners are >..< that close to sliding in, but as of this moment, once bored out a tad I am not sure how much of the lower liner will go in, as just below the case half is the crankshaft bearing support material (and its tapered to the top of the case half. I will look it over the next couple days as I might be able to further shorten the 500/4 liners because of the Tbolt piston mini-skirt, instead of the CB175 nuns clothes :) I'm trying to prevent any removal of structural support. Will take some pics when I get a chance.

The lower section of the liners diameters are (approx):
CB175: 59.4mm
500/4: 62.25mm

Cheers
 

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Discussion Starter #38 (Edited)
I'm guessing you'll need to shorten them, but as long as they don't protrude more than 25mm that's not going to be an issue. I bored the upper case to fit the cb200 barrels and they're 64mm OD

The 500/4 liners are 64mm OD; its the lower section of the liner that pokes through the upper case half, measures 62.25mm (approx). Yes, I will most likely shorten the length of the 500/4 liner to something less than the CB175 liner. I'll put some pics and measurements up when this is done .. next couple weeks:) The 500/4 selection was based on cost, and I get two spare liners ! (for the next build). This is my learn build.. I have four grand daughters keeping an eye on me haha.
 

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Discussion Starter #40
If you cut the chamfer off the lower part of the barrels, you could try Patricks trick of freezing the pistons and rings (compress them with a ring clamp or hose clamp then place them in the freezer over night) take them out, remove the clamp and fit
I plan to have the liner bottom chamfer machined back in after shortening the barrels. I keep reading about the frustration of installing the pistons into the liners, but I think I will try another installation method when the time comes :) I'm several month away from that moment. Hopefully in the next couple weeks I will have the new rods installed on the crankshaft, and following that, fitting the liners in the barrels and modifying the upper case, etc... house refurb duties are keeping me entertained for awhile... (wife's orders haha)

Anyway, learned how to blend out gouges and polish a part; played with some paint too between house refurb breaks....
 

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