Dohc Cb750f: possibly a valve issue

pidjones

Well-Known Member
For polishing.... aluminum? My drill press with belt changed for highest speed and abrasive loaded plastic fiber wheel (for really rough) followed by hand wet sanding with 240 >>>2000 grit followed by cotton buffing wheel on the drill press and jeweler's rouge. All available at Harbor Freight. Patience and elbow grease you supply yourself.
 

teazer

Well-Known Member
DTT BOTM WINNER
10" sewn wheel running at 3,000 revs and use gray (emery) abrasive which they say is for stainless. It should cut through the old laquer and scratches like you cannot believe. Wear gloves and eye protection and hold on tight. Buffing wheels can throw parts across the room if the dig in.

After that go straight to a loose wheel with white rouge and bring up the color. Only use wet and dry paper if there is a lot of metal to be removed - and it's still quicker usually to just buff.
 

crazypj

Split personality, I fake being smart
10" stitched cotton wheels takes a hell of a big motor to turn. I use 8" on a 1.5hp motor and can easily stall it out. You don't need to sand to 2000 grit, I find 6~800 plenty when using dark grey or black compound. Use 'loose' cotton wheels and brown compo for primary finishing and an 'open' soft cotton wheel to get mirror finish (also lasts a lot longer between polishing's). Solvol or Mothers is actually too rough for a real good shine after mirror polishing and will dull surface leaving scratches, Use old well used cotton T-shirts, they are softer than re-cycled plastic
If you going to use an electric drill, use 3"~5" surface speed on smaller ones is always too low for a good finish mops.
Sand any real rough stuff with 80 grit first then work up to finer stuff. If you can remove covers (or have spares) use a larger wheel. I often use stitched Sisal with emery compound if I'm not doing any sanding.
Basically you try a higher grit depending on original surface finish, cast or pitted need very rough to cut it down, 'factory' finishes you can generally start with 240 after removing any lacquer or paint.
You can also make emery wheels if you get water based cutting compound, just soften the compound, add a little PVA glue then rotate wheels through 'mud' and allow to dry on the wheel. To reduce cut use ordinary red/brown compound.
The alloy polishing set at HF isn't very good but can be made to work.
Black emery compound from Home Depot is better than any of the other cheap sticks. If your going to do it properly you need to get stuff from Caswell but they are a little pricey sometimes. Oh, BTW, it's great to hear you finally got bike running properly 8)
 

SquidHunter

Active Member
Caswell makes polishing compound? Interesting. I used their tank liner and it was the bees knees. I’ll never use anything else. It was 50 bucks, but it did the job right. I imagine their other products are up to par.
Yeah, the bike has been running phenomenal. I am starting to get some of the typical carb symptoms though. I know it’s coming. I did run some Teflon through a tank. Seems to have made an improvement. I got a big bottle, so I’ll run about 4 oz every three tanks or so and see how it goes. I’m thinking I should check the sync for sure. I’m getting the dreaded clutch chatter


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SquidHunter

Active Member
So today, I get the bike out to tinker with the carbs, I go to start it up and I can’t get it to fire. So I’m like “screw it, I’ll pull the carbs”. With the tank off I found my issue. Bank 3 and 4 choke butterflies weren’t moving. The spring was attached it was just sticking. After I pulled the carbs and fixed that issue, I warmed the bike up good and resynced the carbs..... mmmm mm, buddy she purrs like a kitten. Clutch chatter gone. Idle set perfect at 1100 rpm. And for the first time I did it in under an hour. I hate to say it, but these bike will teach you a carburetor lesson or two


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SquidHunter

Active Member
Since the bike has been running good, I decided to figure out the pannier situation. The last trip I took, I used some soft bags that threw over the seat. They actually held too much stuff. I didn’t use half of it, and they made the bike heavy. They were also sliding up on me as I braked, and I couldn’t use my grab bars to get the bike on the center stand. Pain in the ass packing and unpacking every day. So here’s my idea, and I just used stuff I already had. I cut two sides off a milk crate. I know how it sounds and looks, but as far as functionality goes it’s perfect. I can strap all kinds of stuff to them. I mounted them on some bar mounts, and zip tied the bottom corner to the passenger peg for stability (temporarily, but it actually works well). I used to own a photography business, so I’ve got some nanuk 910 cases laying around. Rok strap that sucker on the panel and go. I like the idea of using things that are easy to come by, in case something happens on a trip I can easily find replacements. My plan is to pack one of my 910s with a film camera set up. The other one will probably be my jet boil and coffee set up or maybe tools, id like the weight to be even. Then I’ll use a roll top on the tail. I’m pretty close to figuring out a tail rack made out of tire spoons that you could use in a pinch, but I’m not quite there yet


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pidjones

Well-Known Member
Wish I'd known your need a couple months ago. I'd have given you my rat bike rack instead of selling it on the bike. Rear racks are sooo useful!
 

SquidHunter

Active Member
I had a rear rack for mine, and now I can’t find the damn thing. The original panniers too. They were pretty rough though


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crazypj

Split personality, I fake being smart
Wow, the original Honda rack and panniers were designed for the bike and look much better than most aftermarket. Even rough they would be a great addition. I've always preferred panniers to a rear rack, never liked having weight way up high and way far back. Really messes up the handling
 

SquidHunter

Active Member
crazypj said:
Wow, the original Honda rack and panniers were designed for the bike and look much better than most aftermarket. Even rough they would be a great addition. I've always preferred panniers to a rear rack, never liked having weight way up high and way far back. Really messes up the handling
I’ll have to find them. I had them in storage, then when we moved back everything is everywhere. I never could get the tail rack to match up right after I took it off. I must have misplaced some pieces. The panniers were already off the bike. They were really rough. I was sure they wouldn’t keep water out, which is a deal breaker for me. My ultimate goal has always been to be able to carry some photo gear. Either way, I do need to locate them


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crazypj

Split personality, I fake being smart
If I remember right, there were a bunch of thick wall spacers holding the brackets in place. The instructions for fitting were pretty comprehensive and easy but I haven't seen them since about 1979. If you can find instructions it will give lengths of spacers from the fitting kit, I doubt the fitting kit will be available anywhere but at least you'll know whats missing
 

SquidHunter

Active Member
Here’s a picture of my set up from today. I rolled my rain gear up in a blanket. I’m planning on using a dry bag about the same size. I really just wanted to test it out. Took this set up on a long ride today, on the curviest roads I could find. Held up surprisingly well. I can’t say I’m 100 percent pleased, but everything functions properly. One case holds my camera gear. The other holds camping/cooking gear. The dry bag on top will hold sleeping and rain gear. It’s a ton less than I carried last time, so it’s much lighter. Center stand still functions. I like it. Let’s camp


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teazer

Well-Known Member
DTT BOTM WINNER
There used to be a rack on the market that came with low or high sissy bars.

Run it solo with a light back on the rack or fit the high sissy bar and slap you big bag on the passenger seat up against that tall sissy bar. For the life of me I can't remember what they were called but they worked well.

With my old T100 I used a bag on the Manx style tank which allowed me to use it as a chest rest on long runs and kept the weight forwards.
 

crazypj

Split personality, I fake being smart
My 550 was faster with a tank bag, obviously helped the aerodynamics. Kinda weird that set up for touring with tank bag plus tent and sleeping bag tied on rear it would do around 130 with less effort than 'naked'
 

SquidHunter

Active Member
A high tank bag sounds like a good idea. When I’m on the road I’m constantly searching for new positions to set in especially around or after the 100 mile mark.


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crazypj

Split personality, I fake being smart
I had a two piece tank bag, lower section straps to tank, about 5" high then top section zipped onto lowert for carrying more stuff. Pack it with whatever that's relatively soft and you can more or less lie on it, 200+ miles no problem
 

SquidHunter

Active Member
Apparently I can load photos again. Here’s my camping set up from this weekend. I only camped one night, and this is all just the things I need. The good: I didn’t over pack, and I carried my favorite film camera and several lenses. The bad: my tent sucks..... it’s a cheap pole tent. It’s small and light and easy to put up, but it’s a pain in the ass to get in and out of it. Also not too stoked on my sleeping pad.

I got a late start and my headlight blew while I was barreling down a dark highway. There’s that. What was worse, the light bulb is apparently made of unobtainium. So here’s what I did right. I pulled over immediately first of all, calmly and slowly. I always pack my bicycle light. It’s actually very bright. I used to cycle a lot and that was my headlight. I zip ties that up, and used it as a temporary headlight to backtrack to a parts store. Like I said, swapping the light bulb would be too easy and of course the didn’t have it. I bought a tool an automotive bung and a headlight (3 prong) for about 40 bucks total and wired that mother up. It took a total of about 10 minutes and I was back on the road. And now I can find lightbulbs anywhere lol. Everything else went well enough. I did feel like the bike smelled a little “rich”, but it ran amazing. Is that possible? No backfires or anything. Cranks fine idle is great. I do think I’m getting a little noise from the front wheel bearings. Definitely going to inspect that further.

Ultimately need this bike to make some real trips. Not because it’s convenient, but more or less for the challenge of it. There’s something about making this bike dependable enough to actually ride is an obsession of mine.

Looks are totally secondary to me at this point


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