71 Indignant CB175 - Complete (w/ pics)!!!

[SeekingZero]

Re: 71 Indignant CB175 - In the midst of painting!

I spent some time today and was working on figuring out the missing connections I needed on the new harness and ordering those. After that I started working on the exhaust. I was able to get the pipes set and tightened with the mufflers on but there are a couple things I don't like about how its sitting.

For one thing, in this picture, I thought those gaps were supposed to line up. Thought I am not that familiar with the CL exhaust.

I also have to work out some kind of bracket to fasten both mufflers together and to the frame.

Finally, both pipes are resting snuggley against the rear shock...is there anything that can be done to fix that, or is that going to hurt anything?

 

[misteroddjob]

Re: 71 Indignant CB175 - In the midst of painting!

I'm assuming your pipes are from a CL175?

If so, it looks like the factory muffler was notched to clear the shock, which would explain why your mufflers are rubbing up against it.

You definitely don't want the mufflers touching the shock.
Both will end up wearing through each other with the movement of the rear suspension.
The other issues is that the heat from the muffler will cause the oil in the shock to heat up and lose its dampening effect, which will make for a bouncy rear suspension.
I think you're going to have to bend the pipes so the mufflers are slightly angled to clear the shock.

Are you going to put a heat shield on the pipes so you don't burn your leg?

 

[SeekingZero]

Re: 71 Indignant CB175 - In the midst of painting!

Crap, I was afraid of that. I tried bending a pipe today and it just would not have it. I will be wrapping the area from the muffler to the top end.

This is what I'm going for.

Even after I bend the pipes, I also have to figure out how to run a bracket to mount it all. That or just leave the mufflers off. I could also cut back the pipes so that it moves the mufflers up...thoughts?

 

[SeekingZero]

Re: 71 Indignant CB175 - In the midst of painting!

Maybe leave the exhaust something like this...

 

[misteroddjob]

Re: 71 Indignant CB175 - In the midst of painting!

In terms of a bracket to support it, take a look at part #8 in the parts diagram I posted.
That should give you an idea how they did it from the factory.

Another idea are these 3 piece clamps:
https://www.denniskirk.com/mh-instruments/black-three-piece-clamp-set.p406932.prd/406932.sku

A long bolt through a spacer to attach a piece of bar stock to the 3-piece clamp should get you close to the mounting brackets on the pipes.

Mcmaster-Carr has all kinds of spacers up to 2 inches long
http://www.mcmaster.com/#unthreaded-spacers/=nsp1u2

Maybe take the pipes to a muffler shop and have them bend them slightly on their pipe bender.

Another thought:
I'm not familiar the Honda twin engines, but most engines lose power with unbaffled straight pipes unless they're heavily modified. You'll also notice the exhaust on multi-cylinder bikes almost always converge at some point so there's a scavenging effect between the cylinders to increase low end torque. If you look at the parts diagram again you'll see the stock Honda exhaust converges at the muffler, which is probably to maximize the performance.

You could have the muffler shop bend a Y-pipe that converges both pipes into one:
http://www.summitracing.com/parts/wlk-41357/overview
Could be bolted between the pipes and muffler or have them weld it onto the pipes. Of course, you'd have to repaint the exhaust.

 

[SeekingZero]

Re: 71 Indignant CB175 - In the midst of painting!

Hmm, some good points. As a friend told me, I'll have to sit on the throne and ponder it more.

I really want to go with the mufflers because I love the way the bike looks sitting now. I don't know about whether or not these twins would benefit from the joined exhaust...that seems a question for someone like Sonreir, if I could get him over to this thread. I haven't seen it done much, but then again, most people that build up these bikes have no idea what they are doing...and I must admit, I'm half guilty of that.

I may go by an exhaust shop next week and see what those guys think. Right now I can pull the pipes with my arm and clear the shock, but of course it moves right back. I would think if those guys can just bend the pipes out an inch, I can get the clearance I need and run some flat stock down to hold everything in place.

Let me know if you have any more ideas as I continue to ponder. ;D

 

[Barnburner]

Re: 71 Indignant CB175 - In the midst of painting!

I am no expert but I have read many times that these bikes do well with a 2-1. In fact, many of the 160s and 175s being raced sport one. I am currently running EMGO shorties like yours on my CL175. I cut back the headers a few extra inches so the narrower tip would be by the shock, which helped with clearance.

 

[misteroddjob]

Re: 71 Indignant CB175 - In the midst of painting!

I like it better with the mufflers too.
I know the exhaust shop will be able to bend them for you, which would solve the major issue.
I'd recommend wrapping the ends with painter's tape and drawing some lines with a Sharpie on the top and bottom so the muffler shop knows what direction to bend.
Don't think too hard while you're pondering...

 

[SeekingZero]

Re: 71 Indignant CB175 - In the midst of painting!

I am no expert but I have read many times that these bikes do well with a 2-1. In fact, many of the 160s and 175s being raced sport one. I am currently running EMGO shorties like yours on my CL175. I cut back the headers a few extra inches so the narrower tip would be by the shock, which helped with clearance.

I have noticed the same thing on a lot of the race bikes, though most have complete custom exhausts. Right now I just want this one to go down the road and run up to 65mph.

How does the performance fair on yours? Did you notice a difference before and after? I really like the mufflers past the shocks, but of course, modification would need to be made.

 

[SeekingZero]

Re: 71 Indignant CB175 - In the midst of painting!

I'd recommend wrapping the ends with painter's tape and drawing some lines with a Sharpie on the top and bottom so the muffler shop knows what direction to bend.
Don't think too hard while you're pondering...

Excellent idea, and good point!

 

[misteroddjob]

Re: 71 Indignant CB175 - In the midst of painting!

I am no expert but I have read many times that these bikes do well with a 2-1. In fact, many of the 160s and 175s being raced sport one.

I immediately thought of the Vicious Cycle guys who specialize in racing the cb160s.
Here's one with the 2 into 1.
Notice that the pipe continues after the muffler under the tail. I dig it.

 

[SeekingZero]

Re: 71 Indignant CB175 - In the midst of painting!

I immediately thought of the Vicious Cycle guys who specialize in racing the cb160s.
Here's one with the 2 into 1.
Notice that the pipe continues after the muffler under the tail. I dig it.

Well, I guess you know your shit! That has everything you talked about, 2-1 Y, muffler, etc.

 

[misteroddjob]

Re: 71 Indignant CB175 - In the midst of painting!

Wow, so I guess you know your shit! That has everything you talked about, 2-1 Y, muffler, etc.

I might spend too much time on the throne pondering.
Actually, everything I've learned about exhaust was due to a PM I got from Swivel.
He told me the exhaust on my bike wouldn't work, which started me on a quest to learn everything I could about exhaust design.
I'm no expert by far, but I think I have a decent understanding of what works best.
Ahh, Swivel, I kind of miss him.
He wasn't all bad, just mostly.

 

[Big R]

Re: 71 Indignant CB175 - In the midst of painting!

Don't know why I haven't posted before here.....

I tried running separate exhausts on my CL175 and it always bugged me. Once I had a 2-1 muffler installed, it smoothed out the motor a lot. I figured the engine isn't making a lot of power to begin with so every little bit helps.

I wonder if you could use any CL muffler (175, 350, 450, etc)?

 

[SeekingZero]

Re: 71 Indignant CB175 - Exhaust Pondering...

Don't know why I haven't posted before here.....

I tried running separate exhausts on my CL175 and it always bugged me. Once I had a 2-1 muffler installed, it smoothed out the motor a lot. I figured the engine isn't making a lot of power to begin with so every little bit helps.

I wonder if you could use any CL muffler (175, 350, 450, etc)?

Well join the party!

So you're telling me that I need to go 2-1... I may see what the muffler shop can do. What do you guys think of an H-pipe? Like they use on the Mustang exhausts... Have the shop bridge the two pipes with an H before the mufflers, then I wrap that and done. Think it will provide the same kind of scavenging effect?

 

[Big R]

Re: 71 Indignant CB175 - Exhaust Pondering...

Ask them what they can do! Can't hurt.....unless:

Ben, you'll have to forgive my ignorance (my 175 was a 1968 "sloper"). But if your headers are welded together with a crossover pipe, will they still clear the down tube in front of the engine?

 

[SeekingZero]

Re: 71 Indignant CB175 - Exhaust Pondering...

Ask them what they can do! Can't hurt.....unless:

Ben, you'll have to forgive my ignorance (my 175 was a 1968 "sloper"). But if your headers are welded together with a crossover pipe, will they still clear the down tube in front of the engine?

The crossover wouldn't have to be on the front. I was thinking of it on the side...about where your leg would be. Then no clearance issues and hardly noticeable. However, I still don't know if this would provide the same effect or bee worth while. If the performance hit the bike would take from just running the pipes straight through like they are now is negligible, then I'm not going to worry about it on this bike.

Like I said, end goal is running and 65 mph.

 

[Big R]

Re: 71 Indignant CB175 - Exhaust Pondering...

Oops, maybe I wasn't clear. I have an aftermarket 2-1 on my 650, and there is a slip joint at the Y connector so the headers can pivot away from each other. Without that pivot point, the headers can't be moved past the down tubes - they need to be spread apart. I didn't know if the vertical 175 motor / frame was the same way.

 

[SeekingZero]

Re: 71 Indignant CB175 - Exhaust Pondering...

Oh I see what you mean. Ya I think you have a point.

 

[SeekingZero]

Re: 71 Indignant CB175 - Exhaust Pondering...

So I just thought of something. The CB175...from the factory, has two separate single exhaust pipes with individual mufflers. So apparently its going to run fine without having the pipes joined in some way.

I'm just going to take the pipes to get bent out a bit, make a bracket, and be done with it.