Topic: Almost there, except for the pipes...

[ZTatZAU]

My K1 750's resurrection is almost complete or at least as complete as such projects ever are...  Except for the set of no-stamp Busso pipes, I've been putting off for last.



I'm currently focused on fitting the two inside pipes (#2 & #3) as they are about the same amount off at the rear foot peg mounting hole.  With the #2 pipe snug up against the exhaust (spigot) flange...



... As others have found, the rear of the pipe looks like this at the rear foot peg mounting hole...



i've used a 6" piece of 1/2" EMT to center the stepped down foot peg bolt in the muffler's sleeve.  The EMT fits snuggly in the sleeve and the fat portion of the 14mm bolt fits snugly in the EMT.

As the pictures show, I need the bolt to move aft about 1/2 of the hole's diameter.  That is, 14mm/2 = 7mm, in order to center the foot peg bolt in the hole of the frame.  Pipe #3 on the other side is slightly, (about 1mm), closer.  My questions are...

1) Is there no other way to move the mounting bolt 7mm aft, other than removing 7mm from the slotted outside barrels at the spigot end of the pipe?

And pardon me for asking this but...
2)  Does removing 7mm from the flanged spigot end of the pipe (and the inner pipe as required) to allow the pipe to move further on to the spigot, result in the same amount of movement and direction when measured from any point on the pipe?

I should also mention, the mounting sleeves in the Busso mufflers are slightly oversized.  (I.E. By the wall thickness of 1/2" EMT).  So, there is some wiggle room.  Should I ignore this wiggle room when modifying the pipes to center everything up or "cut less" hoping to take advantage of the excess clearances?

As always, thoughts, comments and suggestions appreciated.
ZT

[seanbarney41]

Always, if there is any question, cut less first.  Then you can always cut more if you have to.

[BenelliSEI]

First; Bike looks fabulous, way to go! Do you have the correct bolts that go in  there? Or are you planning on using the EMT as a spacer?

I have a 24” pry bar that’s about 3/4” diameter and tapers down to about a 3/8” point at one end. It’s just right for sticking through the pipe bushing and jamming into the frame hole. Using the bars leverage, I’m always amazed how much the pipes will flex and move backwards or frontwards. If I can line it up with the bar, I then use  a mix of axle tie down straps, bar end straps and ratchet straps to position the pipes and get the bolt in there (forget the foot peg for now). Tighten it all up and after a few rides (heat cycles), the pipe stays where you forced them to go….. This works for a surprising amount of misalignment.

Looking at your picture, I would not cut anything. That’s a “normal” outage. Just “Make it fit”. If it helps, file a small ramp on the leading edge of the frame bushing to help the bolt get in there. This is one job where a little aggression is often required.

[BenelliSEI]

I just reread your post. Are you wrapping the emt around “a bolt” or the correct bolt? If the correct bolt, get rid of the emt. Take advantage of the oversize hole. Once you have it all bolted down it will not rattle and no one can see it.

By correct bolt, I mean the one that belongs there. I assume you have a pair? It has a massive shank and tapers down to the thread size at the inboard end. Those two bolts are unique to that location. I have a few pairs I can photograph if you want to see a set?

[Don R]

 I believe the Honda and my Yamiya rear mount sleeves were also slightly oversize, one set had an angular offset between the two mufflers mount tubes which required me to ream the difference with a drill. I also used a small ironworker's pin wrench to align the holes and may have added a bevel to the entry point of the frame hole to help the bolt find its way through.
 Yes, I am a cheater. I agree with everything posted above also.
 If the pipe says no, I carefully suggest that it change its mind.

[BenelliSEI]

“I carefully suggest that it change its mind”. 😂

[RAFster122s]

ZTatZau, gorgeous work on the bike! Good luck surfing the exhaust...

[ZTatZAU]

Thanks everyone!  I appreciate your replies and nice comments.

First; Bike looks fabulous, way to go! Do you have the correct bolts that go in  there? Or are you planning on using the EMT as a spacer?

Yes!  I do have a new set of the correct Honda bolts.  The EMT was used to center everything up so I could get a good measurement for what I had reluctantly resigned myself to be cutting.

I have a 24” pry bar that’s about 3/4” diameter and tapers down to about a 3/8” point at one end. It’s just right for sticking through the pipe bushing and jamming into the frame hole. Using the bars leverage, I’m always amazed how much the pipes will flex and move backwards or frontwards. If I can line it up with the bar, I then use  a mix of axle tie down straps, bar end straps and ratchet straps to position the pipes and get the bolt in there (forget the foot peg for now). Tighten it all up and after a few rides (heat cycles), the pipe stays where you forced them to go….. This works for a surprising amount of misalignment.

Looking at your picture, I would not cut anything. That’s a “normal” outage. Just “Make it fit”. If it helps, file a small ramp on the leading edge of the frame bushing to help the bolt get in there. This is one job where a little aggression is often required.

I sure like the sound of all that John!  Come on over!  Don't forget your pry bar!   

Couple of questions...

1)  What if anything, do you do up front, while you're moving the back end around with your prybar?

2)  I'm trying to visualize the tie down/ratcheting straps you described and how and where you're attaching them to be able to insert the bolts.  Can you expound a bit on that?

3)  I've not removed or messed with my exhaust spigots, other than a good cleaning, and can only go by the parts book to understand what that exhaust port gasket behind the spigot seals.  Does the gasket only seal the spigot or is it also supposed to seal the end of the inner exhaust pipe that goes inside the spigot?

I ask this to know if the inner pipe must be trimmed to a specific length if you wind up trimming the outer slotted bell of the pipe?  Or must the inner pipe only be trimmed enough to allow the outer bell to bottom out on the spigot?

Thanks once again!  ZT

[newday777]

#3 The copper donuts seal the exhaust spigots to the head.

When I tried to test the fit of my busso pipes back in March, it appears the inner pipes and outer slotted bells will need to be trimmed shorter to allow the muffler bolts to fit to the frame holes.

[ZTatZAU]

#3 The copper donuts seal the exhaust spigots to the head.

When I tried to test the fit of my busso pipes back in March, it appears the inner pipes and outer slotted bells will need to be trimmed shorter to allow the muffler bolts to fit to the frame holes.

Thanks Stu!  I appreciate your reply!

Was your mis-alignment at the rear bolt any better or worse than what's shown in my pix?

ZT

[BenelliSEI]

Stu answered your question. I have two sets of handle bar tie downs which I use when strapping a bike in my trailer. They are soft 1” straps, sewn into a long “8”. Usually I put them over the handle bars and hook a tie strap through the looped ends…..

For the pipes I wrap one a few times around the spot where the head pipe joins the muffler (so it can’t slip back). Looking at your photo, I’d put a ratchet strap back the left side lower shock clevis and crank away….. Or the grab handle if you want it to come up as well…. Be creative and take your time. I would not cut anything at the front until you determine it is absolutely necessary.

If my description makes no sense, let me know. I’ll mock one up and take a picture.

[BenelliSEI]

Just looked at you photos again. Pull back to the lower shock mount.

[ZTatZAU]

^^^
Got it!  Thanks John!
I'll give all that a try and report back!

I'm thinking about a certain tire iron, that's around here somewhere, that could make a good muffler alignment prybar.  I'll have to find some ratchet straps to do the pulling.

ZT

[Tracksnblades1]

Beautiful build ZTat…😇

I read now you can encourage 4/4 pipe alignment. 🤔
Wasn’t I told not long ago that was a no/no, you couldn’t tighten nothing until everything line up…
Now I read, “you can” heavily persuade alignment… Did I miss something before..? 😏

[newday777]

#3 The copper donuts seal the exhaust spigots to the head.

When I tried to test the fit of my busso pipes back in March, it appears the inner pipes and outer slotted bells will need to be trimmed shorter to allow the muffler bolts to fit to the frame holes.

Thanks Stu!  I appreciate your reply!

Was your mis-alignment at the rear bolt any better or worse than what's shown in my pix?

ZT

About the same offset

[Don R]

  I've had a Yamiya pipe that far off, but the other way. It may have been a bike issue.
  I'm still hoping to get a set of pipes this close to fitting.
  No one in Italy is going to help, if I was closer, I'd jump in, being a pipefitter/welder that usually had to suffer with new apprentices for help I spent a career making things fit that didn't want to.
 

[Don R]

 Trying to start all of the bolts and clamps before tightening anything is still the best procedure whether it's a Honda 4-4, a car exhaust system or any other multiple fitting assembly.
 I spent an evening under an Impala station wagon with dual exhaust that my wife and sister put on, they were so proud except every joint was only halfway together. And tightened, and rubbing the rear axle. I wore out a 4x4 with a 3lb. hammer shortening that thing enough to not rub. 

[ZTatZAU]

...Looking at your picture, I would not cut anything. That’s a “normal” outage. Just “Make it fit”. If it helps, file a small ramp on the leading edge of the frame bushing to help the bolt get in there. This is one job where a little aggression is often required...

I would not cut anything at the front until you determine it is absolutely necessary.

Hat's off and kudos again to you John, for urging me to do a little more pulling and tugging before cutting anything!  My Busso #1 and #2 pipes are now installed using your suggested methodology and physical persuasion.     No cutting, no drilling, no grinding!



I still need to tweak things a bit to optimize the fit and clearance as I hear a slight rattle when I bang on the tail end of either pipe with my fist.  I'm pretty sure the rattling is the outboard edge of the #2 pipe at the frame behind the side stand mount.  If I can rotate #2 slightly, away from the frame, that should help improve the connecting tube line up... which is currently livable but a little off.  Fingers crossed for luck!

I am wondering now about the passenger foot peg and what I may be missing or do not understand about how the foot peg is supposed to lock in the up and/or down position.  Best I can figure is that the rectangular ring is supposed to exert a little springy pressure on the flat sides of the mount but give way to ride over the curved surface of the mount to go down or up with the peg.  Unfortunately mine do not!



Is the rectangular ring supposed to have a bend in it one way or another to exert some pressure on the mount?  Mine appear to be completely flat.  Any tips or suggestions are welcome on this.

I've also put off grinding a relief slot on the bottom of the #1 muffler's sleeve/bushing to accommodate the little indexing plate on the back of the peg mount.  It looks to me like doing so would allow the peg mount bracket to contact the heat shield on the muffler.  So I'm wondering if adding a similar "spacer" on the top of the bolt to maintain the small stand off clearance I do have.  I sure hope that makes sense and any tips or suggestions on this are also welcome.

ZT

[CycleRanger]

The rubber on the footpegs has shrunk with age.
Use an o-ring between the rubber and the square washer to make up the difference.

[ZTatZAU]

The rubber on the footpegs has shrunk with age.
Use an o-ring between the rubber and the square washer to make up the difference.

Thanks CR!
I'll give that a whirl.
ZT

[Don R]

 I thought I invented the O-Ring trick. Great minds work alike, L0L!  I've also lubed the inside of the rubber with silicone spray.
 I'll check clearance to the shield before I cut the footpeg notch.
  My wife asked if anyone had successfully installed any of these no number pipes that she heard me complain about for nearly a year. In her credit she never once said way to go, dumbass! I have not gotten caught up in the shop yet.

[CycleRanger]

I thought I invented the O-Ring trick. Great minds work alike, L0L!  I've also lubed the inside of the rubber with silicone spray.

You probably did and I probably read about it here. 
I first used o-rings on my 750K5's floppy foot pegs probably back around '09.
Simple, elegant, and effective.

[grcamna2]

I'm not certain if it applies,but would it help to loosen all the engine mounts just enough to where the engine could be lightly pulled with  straps or jacked a little to align the fit of the pipes ?

[BenelliSEI]

“Hat's off and kudos again to you John, for urging me to do a little more pulling and tugging before cutting anything!  My Busso #1 and #2 pipes are now installed using your suggested methodology and physical persuasion.     No cutting, no drilling, no grinding!”

Thanks, and well done! On the pipe that is rattling or buzzing on the frame: try loosening off the rear footpeg bolt completely. Find a slim piece of wood you can jam between the frame and pipe (I’ve used a small piece of wood cut off a flat paint brush handle). Tighten everything backup and after a few rides, the wood usually disappears…. If not, pull it out. You’ll find the clearance you want has been generated by the heat and pressure. These pipes are mild steel and it does not take much to alter their shape a tiny amount.

Simplest solution to the rear footpegs is new rubbers.
Your bike looks really terrific!

[ZTatZAU]

I thought I invented the O-Ring trick. Great minds work alike, L0L!  ...

You probably did and I probably read about it here. 
I first used o-rings on my 750K5's floppy foot pegs probably back around '09.
Simple, elegant, and effective.

Simplest solution to the rear footpegs is new rubbers.

Thanks again for the tip!  3/4" x 1/8" O-rings worked great and are essentially invisible. And while they might be  a tad short, my rubbers are not worn and still look pretty good; so the o-rings are the perfect solution for me.

And those rubbers must shrink up pretty fast.  I seem to recall the passenger pegs on this bike were flopping around in the 1970's.

I'm not certain if it applies, but would it help to loosen all the engine mounts just enough to where the engine could be lightly pulled with  straps or jacked a little to align the fit of the pipes ?

Can't remember who posted it, but someone here posted a step by step to installing 4-4 pipes and the step #1 was to loosen all the engine mounts.  I'm still holding that procedure in my reserve bag of tricks; but only as a last resort so as to avoid any unintended alignment changes.

Thanks, and well done! On the pipe that is rattling or buzzing on the frame: try loosening off the rear footpeg bolt completely. Find a slim piece of wood you can jam between the frame and pipe (I’ve used a small piece of wood cut off a flat paint brush handle). Tighten everything backup and after a few rides, the wood usually disappears…. If not, pull it out. You’ll find the clearance you want has been generated by the heat and pressure. These pipes are mild steel and it does not take much to alter their shape a tiny amount.

Appreciate the nice comments John!  I made good use of two different sizes of paint stirring sticks (1/8" and 1/4" thick) just as you described to mitigate the rattling on the left side.  I'm considering pipes 1 & 2 complete... for now... except for the observation noted below in reply to Don R.

Your bike looks really terrific!

You're too kind John and might feel different if you got a little closer.  But it is what it is and I'll be tickled to get it back on the road again.  My first and current wife of 52 years and I, fell in love on this bike back in 1972.

...  I'll check clearance to the shield before I cut the foot peg notch.

I'm really looking forward to hearing what you find when you tackle your pipes Don.

As I mentioned above, my left side is essentially done and I thought pipes 1 & 2 were going to be the most difficult.  Not so, in my case.  On the right side, I can make the #3 & #4 rear holes a little easier than on the left, but I'm having a hard time getting the #4 pipe to tuck in as close as I think it should be up front and achieve a good line up on the connecting tubes in the rear.  I'm thinking the problem is a lack of clearance where the #4 pipe passes under the brake pedal pivot.  It seems to me like the cut-out in the muffler needs to move aft... so the muffler can move inward as much necessary without impacting the brake pedal when things are tightened up.



I'd like to know where, on a stock K1, the #4 muffler weld seam lies (inboard or outboard) in relation to the clamping portion of the brake pedal?  Is the muffler seam supposed to be inboard or outboard of the brake pedal clamp bolt?

Now, as to checking for clearance between the peg bracket and heat shield, before cutting your notch...
I strongly suggest you take a good look at the total combined length of the two muffler mount sleeves and peg bracket in comparison to the length of the OEM Honda bolt.

On my left side, with everything tightened up as much as I dare, there is only room for a flat washer under the nut with not enough space for a lock washer.  I haven't got that far yet, on my right side, but I do know the outer muffler sleeve is long enough to cut a notch without impacting the heat shield.  (About twice as much clearance as on the left).  This makes me question the accuracy of the placement of the mounting sleeves in the individual mufflers.  Is it possible that rather than modifying the front end of these pipes, it may be necessary, in some cases, to modify the mounting sleeves which may be too long or mis-located so as to prevent a proper tightening with all the specified hardware???

ZT