GZ125 larger front wheel

[waxmonkey]

I know I know it’s only a 125 and why bother but it’s something I use just to nip though the town traffic in the summer

So I’m on striping it and modding it just cause a want to

I’ve already extended the rear swing arm on 4inch and currently on mocking up a single rear shock and spring central to give a cleaner back end

So front wheel question what other Suzukis rum the same type of wheel looking to increase to at least 19inch 21 iff possible

Also stuck on rear sprocket needs stepping out 10mm, ideally was hoping to find a dished sprocket or even a spacer but having no luck so might have to use the lathe for a few hours to turn something instead
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Steve B

[Nobby the Bastard]

Sooo, you are taking a swing arm that normally has shock absorbers connected to the end and putting a mono shock right at the front, and then compounding the error by extending the length of the swing arm, thus increasing the leverage generated on an already spindly swing arm?

Can you make sure someone is videoing you the first time you go over a bump? I would imagine the immediate loss of the rear wheel due to failure of the swing arm will be quite spectacular.
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trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint ST 1050

[WD Forte]

Wow, those sound like fantastic improvements
any pics?
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bikers smell of wee

[waxmonkey]

Tipical negative response where is the spirit of pushing the boundaries and trying something new
Of course the rear swing arm has been completely re-fabricated from scratch beefed up and more the up to the job along with the rear suspension which has been match to the machine weight and additional forces which be present

Now back to the front wheel. Do you actually have a solution or just happy to come on here to try to belittle people doing something different
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Steve B

[Nobby the Bastard]

No. My 160 mph 250 kg Triumph manages quite happily with it's 18 inch wheels so I'm not in the market for putting bigger ones on it.

Beefed up? It'll need fuck loads more times it's original strength to prevent it flexing like Hulk Hogan in front of a mirror....
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trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint ST 1050

[Easy-X]

A big front wheel is usual for dirt bikes, e.g. DRZ400:

https://upload.wikimedia.org/wikipedia/commons/thumb/e/e2/NSW_Police_Suzuki_DR-Z400E.jpg/640px-NSW_Police_Suzuki_DR-Z400E.jpg

I'll go out on a limb and say it's to "bridge" gaps you might be riding over. What about tarmac? Let's take a look at a DRZ400SM:

https://upload.wikimedia.org/wikipedia/commons/thumb/c/c4/2007_Suzuki_DRZ-400SM.jpg/640px-2007_Suzuki_DRZ-400SM.jpg

Different tyres obviously but is it me or do those wheels look smaller?
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Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[Nobby the Bastard]

Those are road size wheels put in a dirt bike frame or 'supermoto' as they are called in the trade.

The wheels will be 18 inch, the same as virtually every fucking road bike in production.
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trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint ST 1050

[WD Forte]

The bigger front wheel on dirt bikes is usually fitted with a lower profile tyre which won't deflect too much and cause steering control issues.
The overall diameter is roughly the same as the higher profile rear.
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bikers smell of wee

[Nobby the Bastard]

I suppose we should get scientific about this.

Torque is a factor of distance and force applied.

Assuming the same force applied, we can calculate the increase in torque by moving the fulcrum (where the shock is attached.)

The original shocks are about 2 inches up the swingarm from the spindle where all the force is apllied. So, to calculate the increase in torque all we need to do divide the distance to the new fulcrum (shock) from the spindle by 2.

In order to ensure room for mounts, clearence for tyre etc for an 18 inch wheel you really need 12 inches added in, 9 for the wheel and 3 for the tyre. With the addition of 2 inchesfor bracketry, tyre expanding whilst spinning etc. you get about 14 inches from spindle.

So 14/2 shows that the force applied at the fulcrum is 7 times what it was originally.

Then you made it 4 inches longer, we are now at 9 times.

Just how much bracing did you do down the whole length of the swing arm?
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trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint ST 1050

[WD Forte]

Here's a GZ125 with bigger wheel/smaller tyre
Note the absence of a front mudguard.
Pfft! who needs mudguards? mudguards is like well gay innit

https://auctions.afimg.jp/f1051719438/ya/image/f1051719438.1.jpg
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bikers smell of wee

[waxmonkey]

A lot is fabed from 6mm plate in comparison to the 2mm as standard

I’m just looking for some help as finding info on what is new or different isn’t easy

Just after if any one knows if there’s a larger front wheel which bolts in and has the same holes etc for the front disk
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Steve B

[Nobby the Bastard]

Nope, I'm here for the belittleing.

How much unsprung weight have you added with your 'cleaning up the back end'?
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trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint ST 1050

[stinkwheel]

GZ125 has a wire wheel yes? Might be easier to just lace a new rim onto it?

If you have a lathe and enough machining knowledge to use one, you could fit pretty much whatever wheel you want as long as it fits between the forks and has a single disc. Couple of new spacers and perhaps a spacer plate to move the calliper if it doesn't align with the disc properly.

DR350 wheel might be worth a look, but any 21" wheels will probably have an alloy rim.

You do know if you modify the frame you'll need to re-register the bike as a radically altered vehicle and have it put through an MSVA test and register it on a Q-plate.

If it has a modificed frame, it's radically altered. If it has the original, unaltered frame it must have at least two of the following:
Forks
Wheels
Engine or gearbox
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Nobby the Bastard]

If you are able to basically create a swing arm of a suitable size to a suitable standard then you work in the trade.

You wouldn't be asking what would fit such a common bike here, you would be asking within the trade.

I'm expecting that your 're-fabbing' will in reality look like the one time I tried to weld up my side stand and cut the fucking thing off instead.

Basically if weld was Diarrhea it would look like that.
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint ST 1050

[waxmonkey]

Come on people I was just asking for some help, yes I’m a good fabricator done steel work for many years

I know lots of fabricators in the steel trade but not the motorcycle trade

I don’t have the knowledge of many different bikes so was simply asking if any one new of a larger wire wheel which carry the same fitment

Nobby have you nothing better to be doing as I’m guessing you know very little or you would have come up with a solution

Will have a look at the dR350 thanks for that stink wheel
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Steve B

[Easy-X]

If you started a conversation with "I'm after ideas on how to murder my mother..." would you expect a good reaction?

I think fundamentally people dislike these motorcycle abortions conversions as it's in the same vein as "we're updating Shakespeare for a modern audience" - changing classical works seemingly just for the sake of it - but it's a dangerous game. One man's avant-garde is another man's idiotic.
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Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[P.]

You'll need to share pics.

But what you are asking for is silly, hence the responses aside from Stinkwheel suggesting that you simply lace a new rim to it... but then the caveat of having it tested as its not standard.

[Robby]

Further to that, getting a new rim and spokes and re-lacing the hub you have is a fairly obvious answer, it's what people have been doing with specials for decades.

If you didn't know about that, the chances are that you don't know what you're doing with a swingarm extension and monoshock conversion.

The monoshock conversion has the potential to be most dangerous in the most extreme situations. You're taking a load that was engineered to be spread across two shocks, a bit further down the swingarm. You're doubling that load by putting it into one shock, then increasing the leverage by extending the arm. You're pointing the top of that shock at the base of your spin, and hoping the top mount doesn't let go under maximum strain - which is generally hitting a bump, at speed, under load. Like what you're doing coming out of a corner.

Cocking around with suspension like this is proper engineering, where you really need to do some maths to know if it is safe. Lacing up a wheel is just home workshop spannering.

That's why everyone is laying in. That and you sound like warped, our own resident engineer fantasist from a few years back. Prove us wrong and people will ease up.

[Ste]

Please post photos of the swingarm and suspension.

[stinkwheel]

[A100man]

ooh - does look a bit flimsy doesn't it. Looks like the seat could be structural.. show us wat you've done so far..

..dare you!

As for the front wheel swap - other than the new rim idea usually folk go for a complete front end swap (yokes/forks etc..) which often means a stem swap from the old set-up. In either case you then have t consider new brake cables or hoses and whether the speedo drive still work etc..
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Now: A100, GT250A, XJ598, FZ750

Then: Fizz, RS200, KL250, XJ550, Laverda Alpina, XJ600, FZS600

[Easy-X]

Just for fun, my favourite Indian bodgers making a bike from scratch:

https://youtu.be/T9Uwl-EItvU
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Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[A100man]

[Easy-X]

Box section and done by eye... old skool At least with the dirt bike they'll probably be doing slow speeds when it does the insto-collapso.
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Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[Nobby the Bastard]

OP will come through with the pictures of their shonky swingarm, I just know it....
____________________
trevor saxe-coburg-gotha:"Remember this simple rule - scooters are for men who like to feel the breeze on their huge, flapping cunt lips."
Sprint ST 1050