Making a bike hit 33hp

[P.addy]

One of my riding buddies has passed his test, but restricted.

He has bought a DRZ400 SM He obviously doesn't want to restrict it, but insurance ask for a cert or dyno. Is there a way to "ruin" the bike so it shows under 33hp on a dyno without using a washer... doesn't want to take it apart

Only makes like..5 or so HP more? So would something like restricting the air intake or spark plug gap affect it enough for it to fly through?

Obviously, he could be sensible and restrict it...but its his licence

[Alpha-9]

Photoshop?

Or are they made on special paper
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Fzr-600 1999

[P.addy]

[KDub]

Throttle stop would probably the best bet. Either wedge something in the linkage at the carb end, or do it at the twist grip (probably easier).
Restrict throttle to something like 3 quarters and it will "fly" through.

[Noxious89123]

Just do a dyno run without opening the throttle all the way?
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'06 Honda CBR125RW-6 ~ '00 Honda CBR600F-Y ~ '07 Honda CBR600RR-7 ~ Bikeless
'53 Ford Ka 1.3 ~ '03 Vauxhall Astra SRi 1.8 ~ '52 Vauxhall Astra SRi 2.2 ~ '53 Vauxhall Astra GSi

[P.addy]

[DrDonnyBrago]

Fill the airbox with socks.

[Alpha-9]

Put socks in the exhaust

Would that work or just make it explode?
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Fzr-600 1999

[J.M.]

[Conzar]

Single cylinder?
Could find out the size for the inlet and buy the right washer from B&Q and drill out a quite a large hole in it then wack it in there?
Not sure if it would work?
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Current ride: ZX6R 636 ------- Previous:KTM EXC 450 Supermoto --- ZX6R B1H --Hornet 600--CBR 600--SV650
11:05:35 Rob Fzs: i just wanna own an rd350 valve before they send us to war with durkadurkastan

[EXC-Rider]

What insurance company is he with ?

Im with carol nash and they didnt even mention about my bike being restricted and its a 600
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owned bikes: DR50, Thumpsta 110 , Honda CR85, Speedfight 100, Yamaha XT125X, Honda CRF450, Honda Hornet '07
current bikes: KTM EXC525 AKA the wheelie machine
A friend in need is a friend indeed but a friend with weed is better!

[Moxey]

[Mikey3]

slacken the chain to extreme amounts

Mike
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'04 Yamaha WR450F
'99 SV650 Streetfighter Project - mid build
'Motorcycling is about what you do; not about what you own, or how much you spend on it'

[bikertomm]

The DRZ is 5bhp over 33?



I thought it was fine on a restricted license?

Ballbag

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07' Honda Hornet now full powaah! My guide on performing an oil change!

[Mil17b]

I doubt it would hit over 33bhp on the dyno anyway.
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KTM 690 SM

[bikertomm]

Just looked it up, apparently the DRZ400 has around 39/40 HP and at the rear wheel 33.4BHP

Where do they want the restriction from.. Wheel or crank ?
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07' Honda Hornet now full powaah! My guide on performing an oil change!

[.Chris.]

I was in a bike shop once when the bloke behind the counter was discussing this very subject with someone on the phone. He seemed to be saying that they'd managed to get the customer's bike under 33bhp by slackening the throttle cable slightly, so that it didn't quite open fully.

That's assuming the bike is standard to begin with. IIRC these bikes are a bit strangled as standard so airbox mods and freer-flowing exhausts are popular.
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Chris
1985 Kawasaki Z550F

[Kickstart]

Hi

Inflate the tyre with water rather than air .

More seriously, is it a slide carb or a CV carb? If a slide carb get a few short pieces of fuel hose. Then experiment putting a piece of it over the throttle cable between the slide and the top of the carb (inside the spring), so it restricts how far the slide can move.

[Rogerborg]

Stuff a sock in the air filter?

Really though, take it to the dyno place and tell them that you're prepared to pay for a printout where their Voodoo Dynomaths shows 25kW. It won't be the first or last time they're asked.
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Biking is 1/20th as dangerous as horse riding.
GONE: HN125-8, LF-250B, GPz 305, GPZ 500S, Burgman 400 // RIDING: F650GS (800 twin), Royal Enfield Bullet Electra 500 AVL, Ninja 250R because racebike

[P.addy]

Will probably see if doing a throttle stop will work

[0l0dom0l0]

Just dyno it.
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CBT Passed: 30/08/2009, Theory Passed: 31/08/2010, Mod 1 Passed: 6/9/2010, Mod 2 Passed: 13/09/2010. Restriction ended 13/09/2012.

Bikes: 2007 Derbi GPR 50, 1998 Yamaha Fazer 600 (written off), 2002 Yamaha Fazer 600, 1994 CBR 600F, 2003 Triumph Daytona 600, Kawasaki ZX6R J1.....Current: 2006 Yamaha FZ6, 1998 Suzuki TL1000R and a Honda VFR 400 NC30.

[Bike Bunker]

or just put the washer's in carb, done this for about 5/6 people now takes you about 25 minutes if that

[SQL]

tbh it probably needs a service before even showing 33BHP, just dyno it and tweak to fit.

[DRZZack]

Instead of messing about with home made restrictions, why not just restrict it then dyno it, then remove the restriction if he wants. I paid £40 quid for the washer and would happily post the dimensions but I can't be arsed taking off the carb again Might have been 42mm Inside Diameter though.

When you're talking about a 3hp difference, there's two arguments - that it's pointless restricting so little, and that it'll be fucking shitty if you have an accident and your insurance company screws you over for the sake of 3bhp.

I rode my drz before and after restriction, and there was jack shit difference (stock), I suppose if he wants to do the 3x3 mod etc and go to town on it there's no point in restricting, but when my insurance costs £900, I don't want it to be void for the sake of 3bhp that I won't miss.

But yeah if he doesn't want to, go to the dyno centre and ask them to go easy on it, the DRZ's are close to 33bhp anyhows. Or jam up the airbox.

[_Iain_]

Couldnt one just simply gaffa tape up most of the inlet snorkel?

Experiment on the dyno roughly how much is needed...but for the sake of 3bhp i wouldnt feck about, just slap the restrictor in there and live with it!
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Please be aware that the above post may be full of complete nonsense.
Riding: '07 KTM Duke II, Baotian BT49QT-20 Driving: '88 Volvo 340