Exhaust Pipe and Kickstart Interference (2009)

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Bonwit

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My old set of pipes had scrape marks from the kickstart lever rubbing against it. I figured it was either mal-formed or misadjusted pipes. Upon installing my new set, I did my best to push the pipe inboard before tightening the nut. So far, so good, but the clearance is very tight, maybe 1/8". Good enough I guess, but I wonder if it will hold

I also see that the top of the kickstart is able to rub on the muffler because there is a little in and out play in the kickstart shaft. I've loosened the kickstart lever and pulled it outboard as far as I can, but I hate to not have full contact with the splines. It occurred to me that perhaps the mounting lugs on these pipes could be a little shorter. Would it help to grind these lugs down a bit in an effort to bring the muffler in more. If so, would a bench grinder do the job without messing up the chrome? Anyone else have this issue?

Thanks
 
It also helps to physically hold the pipe in, towards the frame away from the kicker, as you tighten up the nuts. This makes the difference between hitting and not on mine. Give it a try.
 
Some pipes are worse than others in this regard. Look at the difference in the bends of the right side between factory 750 pipes and some aftermarket ones I bought a few years ago:

Exhaust Pipe and Kickstart Interference (2009)


And the resulting fit at the muffler end:

Exhaust Pipe and Kickstart Interference (2009)


My current pipes are better that but still wouldn't clear the stock kicker. The MKIII kick lever is a must. And my boot scratches the muffler when I kick start unless I'm very careful.
 
BrianK said:
It also helps to physically hold the pipe in, towards the frame away from the kicker, as you tighten up the nuts. This makes the difference between hitting and not on mine. Give it a try.
Click to expand...
I did try that and it doesn't hit (yet) I was just hoping for a little greater clearance.
 
maylar said:
Some pipes are worse than others in this regard. Look at the difference in the bends of the right side between factory 750 pipes and some aftermarket ones I bought a few years ago:

Wow, quite a difference! Wish they still made them like that.
Click to expand...
 
Bonwit said:
My old set of pipes had scrape marks from the kickstart lever rubbing against it. I figured it was either mal-formed or misadjusted pipes. Upon installing my new set, I did my best to push the pipe inboard before tightening the nut. So far, so good, but the clearance is very tight, maybe 1/8". Good enough I guess, but I wonder if it will hold

I also see that the top of the kickstart is able to rub on the muffler because there is a little in and out play in the kickstart shaft. I've loosened the kickstart lever and pulled it outboard as far as I can, but I hate to not have full contact with the splines. It occurred to me that perhaps the mounting lugs on these pipes could be a little shorter. Would it help to grind these lugs down a bit in an effort to bring the muffler in more. If so, would a bench grinder do the job without messing up the chrome? Anyone else have this issue?

Thanks
Click to expand...

I took about 1/4" off the boss's on a set of peashooters. It worked well and the chrome held up fine. Here's some tech tips from British Cycle Supply, it is a common problem.

http://www.britcycle.com/Manuals/norton ... itting.htm
 
I have the same problem on my MK 2 850.

I was contemplating taking a bit off the lugs on the exhaust, but wasnt sure if the thread ran deep enough into
into the exhaust.
So how far does the thread go in , and how much should i chance taking off it.?

If i go for the MK 3 kickstart , is it just a simple matter of unscrewing the old one off or is it more complicated that that. ?
 
For the Mark three I had extended and installed on my bike I just removed the lock bolt, spread the gap a bit with a screwdriver and it pulls right off.
 
I remember that one of the usual (British) spares suppliers was doing thinner exhaust mounting rubbers to cure this problem, can't remember who though, I didn't take too much notice as i've never had that problem on mine, close but not touching!
regards,
Dave.
 
Bonwit said:
BrianK said:
It also helps to physically hold the pipe in, towards the frame away from the kicker, as you tighten up the nuts. This makes the difference between hitting and not on mine. Give it a try.
Click to expand...
I did try that and it doesn't hit (yet) I was just hoping for a little greater clearance.
Click to expand...

In the words of the Prophet, "any clearance is clearance."

Agreed, I just did it again (had the pipes and more off for gearbox work) and didn't think of this first time reassembling. Bing-bing, interference. Loosened the exhaust pipe head nut, held the pipe in towards the frame as I reassembled (tightened up the head nut) and --- no interference. Yes, the gap is small. But again, clearance is clearance!

Good luck with yours.
 
daveparry said:
I remember that one of the usual (British) spares suppliers was doing thinner exhaust mounting rubbers to cure this problem, can't remember who though, I didn't take too much notice as i've never had that problem on mine, close but not touching!
regards,
Dave.
Click to expand...

I have a contact for FD Motorcycles of Dunmow in England who make thinner mounting rubbers.
Phone 01371 876027.
Also I was contemplating taking a bit off the lugs on the exhaust, but wasnt sure if the thread ran deep enough into
into the exhaust.
So how far does the thread go in , and how much should i chance taking off it.?
 
cjatwell said:
If i go for the MK 3 kickstart , is it just a simple matter of unscrewing the old one off or is it more complicated that that. ?
Click to expand...

Straight bolt-on. And for 750 owners, there's added benefit to the extra heft of the 850 kicker. A buddy of mine has actually broken the thinner 750 kick lever a couple of times.
 
cjatwell said:
daveparry said:
I remember that one of the usual (British) spares suppliers was doing thinner exhaust mounting rubbers to cure this problem, can't remember who though, I didn't take too much notice as i've never had that problem on mine, close but not touching!
regards,
Dave.
Click to expand...

I have a contact for FD Motorcycles of Dunmow in England who make thinner mounting rubbers.
Phone 01371 876027.
Also I was contemplating taking a bit off the lugs on the exhaust, but wasnt sure if the thread ran deep enough into
into the exhaust.
So how far does the thread go in , and how much should i chance taking off it.?
Click to expand...
RGM are also doing them 060622 Parallel Exhaust Mounting Rubber.
 
+1 on the Mk III lever. The lever is maybe 3/4" longer than the earlier lever, which doesn't sound like much, but it's about 10%. It also sticks out a good 1/2" farther than the earlier, and I like the fact that it 'self-retracts' - on release the footpeg folds up and stays folded when the lever hits its stop.
 
Hi Bonwit,

I had a joggle put in the right-hand exhaust bracket so the kickstart clears the pipe. I have CAD designs of all the exhaust brackets and you can have them fabricated by your local sheetmetal gent - you're welcome to the files if you want them, (dxf or dwg) just let me know and I'll email them. Alternatively, you can have your own bracket formed in the same fashion, takes about 5 seconds on the bendery machine thingy gizmo.
Exhaust Pipe and Kickstart Interference (2009)
 
davamb said:
Hi Bonwit,

I had a joggle put in the right-hand exhaust bracket so the kickstart clears the pipe. I have CAD designs of all the exhaust brackets and you can have them fabricated by your local sheetmetal gent - you're welcome to the files if you want them, (dxf or dwg) just let me know and I'll email them. Alternatively, you can have your own bracket formed in the same fashion, takes about 5 seconds on the bendery machine thingy gizmo.
Exhaust Pipe and Kickstart Interference (2009)
Click to expand...
A very elegant solution indeed.

When tightening the exhaust nut I did push my leg against the pipe which gave me clearance, but now after riding, I see it's scraping again. Not sure if it's the heat expansion or what. The clearance was pretty tight. I may just grind the lugs, but I am a bit concerned that I might run out of threads.
 
I had a joggle put in the right-hand exhaust bracket
------------------------------

davamb, doesn't that bring the nuts very close to the swinging arm? Virtually touching I would think,
Dave.
 
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