Exhaust valve/flap delete

Monty's Motorcycles

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Hi everyone, I'm aware there have been several posts about this in the past but none recently.
I'm looking at getting a number of kits made up to remove the exhaust flap on the air cooled bikes but just wondering if there would be any interest from members on here?

The kits would come with the tube and 2 new Mikalor clamps to replace the no doubt rotten clamps on the bike. I am thinking a kit at £25 including postage. Does that sound reasonable? Considering the Nippy Norman part is £39 and comes with no clamps.

Please let me know what you think and let me have it both barrels if you like, I can take it :D

Thanks,
Will @ Monty's
 
I admire your entrepreneurial spirit and good luck with the venture.

I went to my nearest stainless steel exhaust fabricators and came a way with a piece of 64mm (2.5”) OD pipe from their scrap bin for £0.
 
Would this be £25 for a piece of machined tube, complete with stops/shoulders inside for the pipes to push up to?

It is it just a piece of stainless tube right dia, right length?

If the latter, you might be up against Ian's solution... If the former, I'd say it sounds good

Sent from my SM-G975F using Tapatalk
 
Slipperyeel said:
Would this be £25 for a piece of machined tube, complete with stops/shoulders inside for the pipes to push up to?

It is it just a piece of stainless tube right dia, right length?

If the latter, you might be up against Ian's solution... If the former, I'd say it sounds good

Sent from my SM-G975F using Tapatalk
Click to expand...

My thoughts exactly, but would also need to be high grade stainless tube and clamps for £20.
At that I think it would be a success.
 
My apologies to the OP.

But!

As this forum is mainly about technical ways of solving problems without the need to shelve out pots of cash needlessly, I feel bound to comment further on the exhaust flap valve.
Much of this has probably been covered already, but as mine seized half closed before I removed it, and after removal I took it to bits to examine it’s construction. I feel qualified to comment.

It is constructed of stainless steel components which are welded together making it a sealed unit and therefore unrepairable. It mainly consists of a butterfly valve just like a throttle body which opens and closes under the control of the separate motor drive module. The valve is biased open via a built in spring. But if the valve seizes, it can stick in any position irrespective of the spring or motor. The spindle for the butterfly valve sits in graphite bearings, but the carbon from the exhaust will eventually cause the bearings to bind. Lubrication may work temporarily, but will eventually burn off leaving the valve sticking or seized again.

So If it stops working:-
Take the plastic cover off and turn the valve anti clockwise until it is fully open and wire lock it in position.
Then disconnect the plug from the control module.
If you want, you can remove the control module and cables.
Job done!
Cost = nothing.
You will probably not notice that it has been disabled, and there will be no indication on the instrument panel either.
However, a test device such as a GS-911 or similar will show a continual fault code. But this can be ignored as it has no noticeable effect on the functioning of the bike engine management system.

If you have the technical ability to purchase an overly expensive after market through pipe and replace your faulty exhaust flap valve, then you have the ability to wire lock your existing valve fully open and disconnect a plug. Either, achieves the same result.

:thumb2
 
Ok, from the sounds of it, it doesn't sound like a great idea.
One of my customers wanted the valve removed as it had seized and the only option I could find (without having the bike with me already to measure the pipework up) was the NN part. I thought their price was way too much for what it is and thought if others wanted to do the same I could provide an alternative.

Machined tube to replicate the original dimensions of the exhaust flap wouldn't be feasible in the volume I would be doing, even at £25 let alone £20. I think I'll get this first small batch sorted and see if I can out them. Nothing ventured and all that...

Cheers for the feedback guys, Ian I presume it struck a chord with you to be replying at that hour :D
 
Monty's Motorcycles said:
I thought their price was way too much for what it is and thought if others wanted to do the same I could provide an alternative.
Click to expand...

And well done for taking the time an effort, you could've saved people some money. And that's what counts. .
 
I fix these. I charge £35 for the process (1 hours labour)

The problem is that the shaft sizes in it's retainer. It's a bad design. The condensation that builds up in the exhaust causes it to corrode.

The solution is to drill/grind off the retaining stub to access the shaft. As soon as this is off, the shaft will move freely again. I TIG weld a nut on the end of the shaft as a safety feature but I don't think it's really needed. I've done quite a few of these.

It's not the prettiest job but it does work and it's better than £200 for a new flap.

The flat is there to increase backpressure/torque at lower throttle positions and also it adjust the exhaust note.

The flaps 90% of the time seize in the open position and most people don't even know it unless they read their fault codes which will record that the servo motor isn't moving. This motor will eventually burn out when the flap is seized. You can hear it buzzing on a bike with a seized flap.

The other solution is to remove it altogether. But make sure you remove the cables from the servo motor too. £25 for the whole kit to do this sounds like a great deal.

Not everyone has a friendly scrap dealer who happens to have a length of stainless tube of the correct diameter lying around. And stainless tube isn't cheap.
 
Monty's Motorcycles said:
Hi everyone, I'm aware there have been several posts about this in the past but none recently.
I'm looking at getting a number of kits made up to remove the exhaust flap on the air cooled bikes but just wondering if there would be any interest from members on here?

The kits would come with the tube and 2 new Mikalor clamps to replace the no doubt rotten clamps on the bike. I am thinking a kit at £25 including postage. Does that sound reasonable? Considering the Nippy Norman part is £39 and comes with no clamps.

Please let me know what you think and let me have it both barrels if you like, I can take it :D

Thanks,
Will @ Monty's
Click to expand...

If you have a kit made up I will buy one - thanks - Alex
 
IIRC I paid about £5 for a piece of stainless steel tube the right diameter on ebay. It was long enough to cut into 3 pieces (2spare) to delete the valve. £25 sounds fair though, for those that can’t search for the piece of pipe and cut it to size.
 
Morning Alex,

I have got some kits made up now, so if you are interested, send me your paypal email and we can get it sorted. I tried to PM you but not sure if I am able to or if it's me being a numpty.

Many thanks,
Will
 
skr80a said:
If you have a kit made up I will buy one - thanks - Alex
Click to expand...

Morning Alex,

I have got some kits made up now, so if you are interested, send me your paypal email and we can get it sorted. I tried to PM you but not sure if I am able to or if it's me being a numpty.

Many thanks,
Will
 
Monty's Motorcycles said:
Morning Alex,

I have got some kits made up now, so if you are interested, send me your paypal email and we can get it sorted. I tried to PM you but not sure if I am able to or if it's me being a numpty.

Many thanks,
Will
Click to expand...

Only just seen this - pm sent....
 
Yes Please

Hi, I would like one of these Flap valve kits if you still have any
Sent you a PM with address

Look forward to hearing from you
 
fitted

Great instructions and a good kit that does what it says on the tin. Flap removed, along with cables, and new link pipe nicely installed. Thanks
 

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Did you make more than a handful of these kits? I can see it was 2 years ago - but only just had the fault code advised so I'm looking for a plan to avoid being stuck in some distant place with a known fault!
 
Ibex said:
Did you make more than a handful of these kits? I can see it was 2 years ago - but only just had the fault code advised so I'm looking for a plan to avoid being stuck in some distant place with a known fault!
Click to expand...

If your bike is pre water cooled, You won’t get stuck, the fault code is advisory, it doesnt stop the bike running.

Disconnect the electrical cable to the control box,
Remove the control box and the control cables.
The valve should stay open under spring tension, but if it’s stuck closed or mid position like mine was, just rotate the cam in the direction to relieve the spring tension and lock it with some wire so it can’t move. The valve will remain in the open position and what little resistance it makes to the exhaust flow is unnoticeable.
You don’t even have to remove the valve.
 
skr80a said:
Great instructions and a good kit that does what it says on the tin. Flap removed, along with cables, and new link pipe nicely installed. Thanks
Click to expand...

I'd be happy to take the (Non) Flappy Valve Section from you for the price of the Postage....
 
Nippy Normans supply Touratech, Wunderlich, Desert Fox and many other makes of accessories.
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