Author Topic: Valve noise (from old board)  (Read 1871 times)

Offline echomadman

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Valve noise (from old board)
« on: March 22, 2005, 12:50:05 PM »
no not that old board, the old old board :)

Valve noise/VVT (from old board)

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shrike
(4/9/02 1:45 am)
Valve noise

Hey, guys!
Just recently bought a 1995 GJ77A two-fiddy and I was wondering. The bike seems to exhibit a little more valve noise than I'm used to from cars. It's the first bike I've ever owned, and it's the only Suzi I've ridden (apart from a '94 GJ74A), but I was wondering, do you guys hear any valve noise from your beasts?

Or do my clearances need adjusting? BTW, bike's only done 16,300kms.

Cheers,
Darren
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bbyrne
(4/10/02 1:46 pm)
Re: Valve noise

That would be the Variable Valve Timing. Have a look a one of the thread in here....we have all had that noise!
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shrike
(4/10/02 9:40 pm)
Re: Valve noise

Sweet, thanks.
Sure sounds loud enough at idle, though!

But then, I guess because it's an unfaired bike, the noises really come through!

Gotta admit, I haven't been above 10k revs too often.

I think that'll have to change, though!
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Steven
(4/26/02 8:55 am)
Re: Valve noise

Unfaired bike does sound louder. but i don't think a 95 bandit has the variable valve yet.. umm.. you would need to check with that. cos the variable valve only came on around 9500 rev. so it should just sound like a normal engine at idel speed. ps, the variable valve engine has a red cam cover.

it it gets excessive loud then you would want to check it. How loud is excessive loud you ask? arr.. @#%$.. how would i know..
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shrike
(4/28/02 8:15 pm)
Re: Valve noise

Yeah, even though my bandit doesn't have a red cam cover it is a GJ77A (the new version) and it DOES have VVT (figure that one out!)

Actually, from the looks of things, it seems a previous owner in Japan removed the red paint from the cam cover (dunno why) as there are red flecks of paint still here and there ont he cover.

Plus, I get the familiar *scratch*scratch* at 10,000
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bbyrne
(4/29/02 4:32 am)
VVT

Defo VVT!! Count yourself lucky....I have a 90 model with no VVT...there is a big power difference.

BB
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leonrider
(4/30/02 4:07 am)
Re: VVT

What part of the power band does the VVT effect?

I was reading about the VTEC system on the new VFR800, and they reckon it improves the bottom end, while peak power is still the same as the non-VTEC model.

just wondering if the Bandit system is similar?
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shrike
(5/1/02 1:22 am)
Re: VVT

I think they both work differently.

The Honda version affects actual valve operation. They have 4 valves, but only 1 intake and 1 exhaust valve work lower down. This improves low down torque. Higher up in the rev range when the engine needs to breathe, the other exhaust and intake valve start operating. In the non-VTEC version of the engine, all 4 valves would operate at all times.

The Bandit's version is like the VTEC system on the older Honda cars. All valves operate all the time, however as VTEC comes on, the valves switch to a different cam lobe with more duration/lift allowing the valves to open more and stay open longer periods of time. Basically doing the same thing as above, but a different method of going about it. This is my understanding of the system, anyway. I could be completely wrong
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Steven
(5/1/02 8:12 am)
Re: VVT

You are right Shrike. The system on the bandit just make the cam lift longer and therefore helping out the high revs (but hurts the fuel eco).

That's why bandit 250's engine love to rev sooo much. If you get a chance to get your bike onto the dyno then you will notice that the power band start to drop at 9.5k rpm, and cam shift came in and makes power again. between 9.7k and 11.1k rpm the engine makes most torque on my engine's dyno graph. and maxium power is at 13.6k rpm.
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leonrider
(5/2/02 4:55 am)
Re: VVT

mine is non-VVT, and is relatively dead under 10 thou.

How much power is a VVT spose to make? The (very uninformitive) import book i got with my non-VVT bandit said it made 45PS...which i think equals about 32kW
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shrike
(5/2/02 8:13 pm)
Re: VVT

Wow. 45ps?

I know the VVT engine was built specifically for the Bandit - I've heard the non-VVT engine was lifted from another bike (Across possibly?).

The VVT engine is supposed to make 40hp (30Kw and ~45ps)@14,500rpm. It starts to pick up around 7-8,000 and really sings over 9,000 (unless you've got condensation in the main jets like I had at one stage. Ever have a bike stutter so badly it almost threw you?).

I'm only going by quoted figures from what I can find (and there's bugger all out there on the net, really)
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RustyAndTheBandit
(5/2/02 9:24 pm)
Power!

I've 'been told' that in Japan, the 250's are limited to 45ps and so a lot of bikes are just quoted as having that power( this might explain why Japanese imports are power restricted).

The older bandit engine looks the same as the across but I've 'been told' that it is actually the engine out of a GSXR 250 which is supposed to be a little bit more hi-per.
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Steven
(5/4/02 10:02 pm)
Re: Power!

On my dyno sheet it is showing a peak power of 34.6hp at the rear wheel. That is with after market exhaust and re-adjust jet. Doing all that didn't really increase the peak power much, only by .4 hp. but every where else there is around 3 hp increase.
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netonci
(5/14/02 5:57 pm)
Re: valve noise

I don`t think that that this `valve noise` should be a problem. I`ve put 22000 km into my bike in 3 years, but nothing changed (service in every 5000 km!!!). You get used to it... Just enjoy
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1990 GSF250 Bandit (currently getting a gsxr400 engine transplant,
2000 SV650S