Honda Twins banner

1 - 16 of 16 Posts

·
Registered
Joined
·
13 Posts
Discussion Starter #1
Hey y'all,

I just bought my first bike to go to and from my college campus off of a neighbor of a friend back home. It's a 1972 CL175 I think K7, but I got it up and running after about a week of work. However, being a dumb college guy with a bunch of confidence I took it out on a bigger road and hit about 60 when things started to go wrong. When it died on me it was doing this weird thing where as I applied more throttle, the engine sounded deeper and less of a clean burn. Turns out that I shredded the Oil Slinger Cap up pretty good because I hadn't thought to tighten it, so I replaced that. After cleaning the points up a bit, got it to fire up again, but now it sounds like s***. I'll attach a video to the thread if I can figure out how to do it, but I'm gonna clean the points up with a finer sandpaper tomorrow and make sure they're good, any other tips would be more than appreciated. I'm still a broke college student so I'm trying my best not to take it in anywhere or order any parts, just trying to make do with what I've got.
 

Attachments

·
Premium Member
Joined
·
24,208 Posts
Welcome aboard, can't help with noises but I'm moving this thread over to Smaller Twins Engine section where it'll get more attention.
 

·
Registered
Joined
·
124 Posts
I think you'd be surprised how little it can cost to do a nice serious tune up to one of these bikes. Especially if you have the time and the know how. First thing I would do is download and print a factory service manual. Google searching should easily find you one. I really can't get much of any sense of what's going on with your bike from what you said or from the video. But with as old as these bikes are they are always worth tearing down and having a close look and installing some fresh parts. How many miles are on the bike?
 

·
Registered
Joined
·
4,770 Posts
Hi and welcome
Sorry for your trouble
Soooo....If the slinger oil cap was loose then the oil pump would be pumping oil into the slinger BUT instead of the oil then passing up to head , it would be pouring back into the sump....No oil to the head wrecks the cam , cam journals, and rockers in about 4min. The noise is all those parts slopping around inside the head.
 

·
Registered
Joined
·
13 Posts
Discussion Starter #7
It's only at 1600 miles, the previous owner got it from a woman who just used it to get around her ranch so it's got an incredibly small amount of miles on it
 

·
Premium Member
Joined
·
3,002 Posts
It doesn't matter how many Total Miles are on the motor.

What matters is the last few were drive at high speed (60 Mph) with little or no Oil going to the top end.

I would remove the Spark Plugs (so you can turn the motor over by hand more easily) then Remove the Valve Caps (there are 4 of them in the Rocker Case)

And get a good small beam flash light and turn over the motor by hand while looking carefully at the Cam Lobes.

If you see anything other than FLAT SHINY surfaces you are in for a rebuild of the top end.
 

·
Registered
Joined
·
13 Posts
Discussion Starter #9
Hey y'all so sorry for the late update on this I've been so bogged down with Ochem, calculus 3, and Chemical engineering exams this past week I haven't been able to find the time to work on the bike. Took off the engine tonight and took a bunch of pictures that I'll attach.

Good news: Everything looks to be in absolutely fantastic condition
Bad news: What is wrong with the bike then? Is it a timing issue? Compression? What's going on?

Any thoughts and ideas are greatly appreciated. I wish I had the money to be able to just throw it at a mechanic and have him figure it out so I could be back out there as soon as possible, but that's just not in the budget. If we can figure out the exact problem and tell them exactly what needs to be done with the only issue being a lack of resources on my end, that may end up happening. The current 3 mile bike ride each way isn't as pleasurable as you might think.

Thanks again, y'all have been awesome!
IMG_9483.jpg
IMG_9482.jpg
IMG_9486.jpg
 

·
Registered
Joined
·
1,173 Posts
THe discoloration on those cam lobes says it got pretty hot at some point. But there doesn't seem be be any gouges or shavings.. so it's probably okay to run. But you really need to determine if oil is getting to the top of the motor after your slinger mishap. Maybe it tore up the springy bit in the cover that presses against the slinger and distributes oil from the pump to the top of the engine. Also, get your valve clearances on , and cam chain adjusted.
 

·
Registered
Joined
·
13 Posts
Discussion Starter #11
It absolutely tore up the cover part, I'll attach a picture of it. About those valve clearances and cam chain, are those things I can do or is that something I take that in for due to the precision tools needed? IMG_9487.jpg
 

·
Registered
Joined
·
288 Posts
You really lucked out! I would have expected that top end to be toast. As Phil said, it got pretty hot but looks ok. You'll need gaskets and the oil filter parts but you can do the cam chain and valve clearance adjustments yourself. You'll need feeler gauges and wrenches. Mostly you'll need the service manual. Get this wrong and you'll surely toast a nice motor.

Do put your location and model of bike under your avatar and sig line. :)
 

·
Registered
Joined
·
13 Posts
Discussion Starter #13
Well, talked to Steve for a while today. He helped me figure out what's wrong with it. IMG_9490.jpg As you can see the camshaft is completely toast. IMG_9489.jpg So is this housing for the points where it makes contact.

Not great at all so I'm gonna need help finding parts for it in a bad way. Steve mentioned a guy who he couldn't remember the handle of that was trying to do the ton on a CB175 or 200 who lives here in Texas (by the way I'm in College Station, Texas) and thought he might be the closest option to finding some nearby guidance.

At least we now know what's wrong with the bike, only problem is that I'm not exactly a rich man, actually the opposite being a broke college student, so this project may unfortunately be sidelined for a little while.

Thanks for all y'all's help
Patrick
 

·
Registered
Joined
·
13 Posts
Discussion Starter #16
Alright y'all I got a bit of money so I'm about to order replacement parts that I found online on ebay. Is the oil filter cap still usable or do I need to replace that too because if possible I'd like to save the money?
 
1 - 16 of 16 Posts
Top