Hi All,

I've just picked up a second hand GX200 powered 3KVA genny and there
is what looks like a fine mesh disk rattling about in the actual
exhaust outlet. It would fall out but it's otherwise trapped by the
other heat shield.

I think the PO suggested there may have been an additional outer
deflector on the exhaust box and I'm wondering if that also had
something to do with holding whatever_this_is in place?

Does anyone have such an engine and know how that area is supposed to
go together please?

If there are some bits missing, would you know if they are available
separately, if not, would one of the aftermarket exhausts on eBay be
ok (ok = no noisier and give full power etc).

On that and if I am going to get a new exhaust anyway, I have here a
fairly new exhaust off a 125cc 4/ scooter [1] that, with a bit of
tweaking and in the spirit of d-i-y etc could be made to fit within
the general genny frame (it's an open cage type). Would you think this
might be quieter than the stock exhaust, if bigger is better it should
be and as I already have it etc?

Cheers, T i m

[1] I think the (125cc) scooter did about 8K rpm and this (200cc)
Honda does about 4k rpm so I don't think the exhaust would be two
restrictive.

"T i m" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> Hi All,
>
> I've just picked up a second hand GX200 powered 3KVA genny and there
> is what looks like a fine mesh disk rattling about in the actual
> exhaust outlet. It would fall out but it's otherwise trapped by the
> other heat shield.
>
> I think the PO suggested there may have been an additional outer
> deflector on the exhaust box and I'm wondering if that also had
> something to do with holding whatever_this_is in place?
>
> Does anyone have such an engine and know how that area is supposed to
> go together please?
>
> If there are some bits missing, would you know if they are available
> separately, if not, would one of the aftermarket exhausts on eBay be
> ok (ok = no noisier and give full power etc).
>
> On that and if I am going to get a new exhaust anyway, I have here a
> fairly new exhaust off a 125cc 4/ scooter [1] that, with a bit of
> tweaking and in the spirit of d-i-y etc could be made to fit within
> the general genny frame (it's an open cage type). Would you think this
> might be quieter than the stock exhaust, if bigger is better it should
> be and as I already have it etc?
>
> Cheers, T i m
>
> [1] I think the (125cc) scooter did about 8K rpm and this (200cc)
> Honda does about 4k rpm so I don't think the exhaust would be two
> restrictive.

I have no idea about the innards of modern bikes or their exhausts, but
exhausts are *supposed* to be designed so that any pressure waves set up in
them assist rather than interfere with the smooth working of the engine.
Each could be said to be 'tuned' for the engine it was designed for. That
said, it has never stopped people going for appearance rather than power and
quietness... - or indeed stainless rather than instant rot and cost a
fortune standard items.

S

On Tue, 25 May 2010 19:27:59 +0100, "spamlet"
<(E-Mail Removed)> wrote:


>>
>> [1] I think the (125cc) scooter did about 8K rpm and this (200cc)
>> Honda does about 4k rpm so I don't think the exhaust would be two
>> restrictive.
>
>I have no idea about the innards of modern bikes or their exhausts, but
>exhausts are *supposed* to be designed so that any pressure waves set up in
>them assist rather than interfere with the smooth working of the engine.

True, although I think that may apply more to 2/'s than 4/'s

>Each could be said to be 'tuned' for the engine it was designed for.

And even tuned further on that particular engine and it's tuning. When
I used to race power RC catamarans a few mm on (or off) the length of
the exhaust could make a big difference.

> That
>said, it has never stopped people going for appearance rather than power and
>quietness... - or indeed stainless rather than instant rot and cost a
>fortune standard items.

The 'factory stock' (stainless) exhaust supplied when we built the
kitcar was *way* too noisy for me so I fitted a slightly shortened ss
aftermarket std Escort one (Grundy?). Been on there over 20 years now.
;-)

My thought on this genny was that the stock exhaust wasn't very
sophisticated (like a lawnmower jobby) and whilst ok a tickover was
quite loud under any real load. If I'm going to replace the exhaust
with a new stock one (this bit rattling makes it annoyingly noisy as
well) I might saw the box off the stub and try tack the scooter one on
with some silicone tube and see how it works.

The thing is I don't know how much mechanical noise is coming from the
engine itself but if I port the exhaust away from the unit a bit I
might be able to soundproof it a touch.

Cheers, T i m

"T i m" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> On Tue, 25 May 2010 19:27:59 +0100, "spamlet"
> <(E-Mail Removed)> wrote:
>
>
>>>
>>> [1] I think the (125cc) scooter did about 8K rpm and this (200cc)
>>> Honda does about 4k rpm so I don't think the exhaust would be two
>>> restrictive.
>>
>>I have no idea about the innards of modern bikes or their exhausts, but
>>exhausts are *supposed* to be designed so that any pressure waves set up
>>in
>>them assist rather than interfere with the smooth working of the engine.
>
> True, although I think that may apply more to 2/'s than 4/'s
>
>>Each could be said to be 'tuned' for the engine it was designed for.
>
> And even tuned further on that particular engine and it's tuning. When
> I used to race power RC catamarans a few mm on (or off) the length of
> the exhaust could make a big difference.
>
>> That
>>said, it has never stopped people going for appearance rather than power
>>and
>>quietness... - or indeed stainless rather than instant rot and cost a
>>fortune standard items.
>
> The 'factory stock' (stainless) exhaust supplied when we built the
> kitcar was *way* too noisy for me so I fitted a slightly shortened ss
> aftermarket std Escort one (Grundy?). Been on there over 20 years now.
> ;-)
>
> My thought on this genny was that the stock exhaust wasn't very
> sophisticated (like a lawnmower jobby) and whilst ok a tickover was
> quite loud under any real load. If I'm going to replace the exhaust
> with a new stock one (this bit rattling makes it annoyingly noisy as
> well) I might saw the box off the stub and try tack the scooter one on
> with some silicone tube and see how it works.
>
> The thing is I don't know how much mechanical noise is coming from the
> engine itself but if I port the exhaust away from the unit a bit I
> might be able to soundproof it a touch.
>
> Cheers, T i m
>

:-) There's me showing my ignorance again: after a garage full of bits on
numerous occasions Honda to me means bike: should have googled first!
Anyhow, always admired the insides of the Hondas, and I expect the general
purpose engines are just as good. I can't seem to make their parts list let
me in (probably a cookie thing), but you can get a manual here if it might
be useful:

http://www.honda-engines.com/Engines...uals/gx200.htm

Looks like plenty of scope for kits with these things if one consults google
images.

Cheers,
S

On Wed, 26 May 2010 00:39:41 +0100, "spamlet"
<(E-Mail Removed)> wrote:


>:-) There's me showing my ignorance again: after a garage full of bits on
>numerous occasions Honda to me means bike: should have googled first!

;-)

>Anyhow, always admired the insides of the Hondas, and I expect the general
>purpose engines are just as good.

Me too. I have a little CB 'Two Fifty' and it starts first press every
time. But then I've always had luck with Yamaha kit. I have a little
2hp Yamaha outboard that weights nothing yet used to put my 14'
sailing dinghy on the plane when one up. ;-)

> I can't seem to make their parts list let
>me in (probably a cookie thing), but you can get a manual here if it might
>be useful:
>
>http://www.honda-engines.com/Engines...uals/gx200.htm

Yeah, thanks for that. It was actually the first thing I Googled for
after getting the beasty. Looking at it again though it does show a
little tail pipe that might be what is missing on mine.
>
>Looks like plenty of scope for kits with these things if one consults google
>images.
>
Yeah, one of the reasons I was interested in this particular genny (I
had the choice of 3) was *because* it was powered by this Honda
engine. Nothing more comforting to stick Honda GX200 into eBay or
Youtube and be inundated with hits. ;-)

If I can get the parts manual my local bike shop can get parts for me
with a bit of discount.

Cheers, T i m

On May 25, 12:50*pm, T i m <n...@spaced.me.uk> wrote:
> Hi All,
>
> I've just picked up a second hand GX200 powered 3KVA genny and there
> is what looks like a fine mesh disk rattling about in the actual
> exhaust outlet. It would fall out but it's otherwise trapped by the
> other heat shield.
>
> I think the PO suggested there may have been an additional outer
> deflector on the exhaust box and I'm wondering if that also had
> something to do with holding whatever_this_is in place?
>
> Does anyone have such an engine and know how that area is supposed to
> go together please?
>
> If there are some bits missing, would you know if they are available
> separately, if not, would one of the aftermarket exhausts on eBay be
> ok (ok = no noisier and give full power etc).
>
> On that and if I am going to get a new exhaust anyway, I have here a
> fairly new exhaust off a 125cc 4/ scooter [1] that, with a bit of
> tweaking and in the spirit of d-i-y etc could be made to fit within
> the general genny frame (it's an open cage type). Would you think this
> might be quieter than the stock exhaust, if bigger is better it should
> be and as I already have it etc?
>
> Cheers, T i m
>
> [1] I think the (125cc) scooter did about 8K rpm and this (200cc)
> Honda does about 4k rpm so I don't think the exhaust would be two
> restrictive.

the screen would be a fire-spark arrestor, they clog up and reduce
engine performance dramaticly, remove it unless you use it near
something that can burn, [ but you dont do that anyway. right]. I
remove my spark arrestors, Ive had motors nearly not run until they
were removed.

On 25 May, 18:50, T i m <n...@spaced.me.uk> wrote:
> Hi All,
>
> I've just picked up a second hand GX200 powered 3KVA genny and there
> is what looks like a fine mesh disk rattling about in the actual
> exhaust outlet. It would fall out but it's otherwise trapped by the
> other heat shield.
>
> I think the PO suggested there may have been an additional outer
> deflector on the exhaust box and I'm wondering if that also had
> something to do with holding whatever_this_is in place?
>
> Does anyone have such an engine and know how that area is supposed to
> go together please?
>
> If there are some bits missing, would you know if they are available
> separately, if not, would one of the aftermarket exhausts on eBay be
> ok (ok = no noisier and give full power etc).
>
> On that and if I am going to get a new exhaust anyway, I have here a
> fairly new exhaust off a 125cc 4/ scooter [1] that, with a bit of
> tweaking and in the spirit of d-i-y etc could be made to fit within
> the general genny frame (it's an open cage type). Would you think this
> might be quieter than the stock exhaust, if bigger is better it should
> be and as I already have it etc?
>
> Cheers, T i m
>
> [1] I think the (125cc) scooter did about 8K rpm and this (200cc)
> Honda does about 4k rpm so I don't think the exhaust would be two
> restrictive.

I don't think the type of exhaust would make a huge difference to a
small single cylinder engine.

I've been thinking of fitting a silencer off a bike to my Yard Man
mower. I've never understood why bike exhausts have been subject to
noise restrictions for decades, but lawnmowers have not. Just think
how much quieter Sunday afternoons would be.

cheers
Richard

On Wed, 26 May 2010 04:47:23 -0700 (PDT), ransley
<(E-Mail Removed)> wrote:


>
>the screen would be a fire-spark arrestor,

Ah, thought it might be.

> they clog up and reduce
>engine performance dramaticly,

Ok.
> remove it unless you use it near
>something that can burn, [ but you dont do that anyway. right].

;-) I don't but there's a possibility it might be going up to Scotland
where my daughter could use it for power tools when finishing her
chainsaw carvings. Would being covered in sawdust and wood-chipping's
be considered a fire risk? ;-)

> I
>remove my spark arrestors, Ive had motors nearly not run until they
>were removed.

Funny you should say that. I went round my BIL's a while back and he
was having issues with a petrol strimmer (lack of power, wouldn't rev
out etc). Once he recapped what he had already done and being familiar
with 2/ motorbikes I investigated the exhaust. As you say, it (fine
mesh) was bunged nearly solid and a good clean fixed it nicely.

Since posting I've found a parts manual for said engine and it looks
like the spark arrestor should have been held in via a small screw
from one side. The missing bit on the outside of the heat shield just
looks like a pressed steel contoured baffle, generally sending the
exhaust gasses downwards.

http://tewarehouse.com/YAM35-25?sc=2&category=60

More interesting (for me) though is I have also found Honda do a
'quiet muffler', all be it for the bigger / V-twin models but it looks
very much like the scooter exhaust I have here.

Like this:
http://tewarehouse.com/19-1090

Also it seems they may do short exhaust stubs that could fit my model
(for other exhaust variants) that would make the task of trying the
scooter exhaust much easier.

http://preview.tinyurl.com/2wxn5ph

(The GX160 seems to share many parts with the 200).

Or I can buy a 'performance' flange and make my own pipe manifold.
;-)
http://preview.tinyurl.com/2vn5pg2

Racing carbs, con rods, all sorts of goodies. ;-)

http://preview.tinyurl.com/3yuvnpn



Cheers, T i m

>
> I've been thinking of fitting a silencer off a bike to my Yard Man
> mower. I've never understood why bike exhausts have been subject to
> noise restrictions for decades, but lawnmowers have not. Just think
> how much quieter Sunday afternoons would be.
>
> cheers
> Richard

You said it! It would be nice to have at least one day a week when we could
actually hear the birds, and maybe even a bee or two. I know there are a
lot of chainsaw enthusiasts out there, but do I have to hear them *every*
day? Even a 'quiet walk in the woods' is often (well was really, I'm a bit
stuck in the house now.) an ear splitting experience these days. Don't they
have a ban on 'Sunday noise' somewhere? Germany?

S

In message <AMaLn.9$(E-Mail Removed)2>, spamlet
<(E-Mail Removed)> writes
>>
>> I've been thinking of fitting a silencer off a bike to my Yard Man
>> mower. I've never understood why bike exhausts have been subject to
>> noise restrictions for decades, but lawnmowers have not. Just think
>> how much quieter Sunday afternoons would be.
>>
>> cheers
>> Richard
>
>You said it! It would be nice to have at least one day a week when we could
>actually hear the birds, and maybe even a bee or two. I know there are a
>lot of chainsaw enthusiasts out there, but do I have to hear them *every*
>day? Even a 'quiet walk in the woods' is often (well was really, I'm a bit
>stuck in the house now.) an ear splitting experience these days. Don't they
>have a ban on 'Sunday noise' somewhere? Germany?
>
Yup - disturb the peace on a Sunday in Krautland and you get a knock on
the door from the boys in green


--
geoff