First Serious Ride

Finally after 10 months struggling with rheumatoid arthritis I got to take my GRiSO out for a decent ride. It runs great. I enjoyed it. But. First thing I notice is how loud it is. It's even louder than my Le Mans with LaFranconi sports pipes. After 45 minutes riding my arse started to hurt. If you've ever ridden a Le Mans for any distance you would know what pain is (like riding a bag of spuds) and I didn't think that could be beaten. Maybe the width of the seat and my short legs have something to do with it. The new fairing is great. No wind what so ever, but I'm only 5'7" so all good. On my return I looked at the Termi exhaust and realised the db killer is missing. Anyone got one or know were to get one? Could I get one made? No doubt the bloke I bought this off won't have it he didn't even have the other key. Anyway can't wait to get this out on some decent roads without the traffic. Cheers

Good onya Stubbie. Unleash the inner hooligan. You might want to talk to Mick at MJM seats in Goulburn. He did my seat for me and I usually ride for at least a tank before I start to feel sore. Glad the fairing works for you too.

Termi dB killers are made out of unobtainium. You can buy all manner of 3rd party dB killers on the eBay. Finding one that will fit could be fun.

Any motorcycle specific exhaust manufacturers in Perth, they could knock one up in 15 min.
We have 4 different operators in Brisbane.

I haven't looked ghezzi but could be. I might give Mario at Thunderbikes a call. He would shurely know. If unobtainium I'll need to get one made. I'm a bit peeved I didn't realise it was missing when I bought it. Wyno I wanted to give it a big handful but decided against as been as it hadn't run for a few months.

I think I’ve got one in a take-off exhaust. If I can guarantee i’d Get it back you can use it as a pattern but the last time I did this for some bloke in Queensland he just took it without even a thank you and fucked off so I’m a bit leery of being generous with shit like this. Sorry, but Arseholes abound.

Pete

You can use mine to get one made. I'm up north for a couple of weeks.
PM me if you have no luck with Mario.
I'm guessing you are local to Perth?
If you are worried about a canary, don't. Numerous traffic stops including busts and not one has mentioned noise.
Giving your bike emphysema when the solution may be ear plugs?

Thanks guys. Pete if I had picked this up a few weeks back you could of bought it with you on your trip out west. I know what you mean. I'm pure as driven snow, so no problem getting it back. I'll follow up locals first and get back to you thanks. Diablo Loco will check with Mario and get back to you thanks. Not worried about others only my sanity.

You’ll find it runs better with the dB killer installed anyway.

Mario at Thunderbikes got 2 termi db killers made up for me. The first one came out during a spirited ride that obviously blew out more than cobwebs. Not cheap but do the job well. Second db killer is there to stay with Loctite and a good blob of silicone just in case.  Cheers Mark

Pete Roper wrote:

You’ll find it runs better with the dB killer installed anyway.

I am wondering in what way it runs better. I am running my GPR with the db killer out. Thanks

It’s down to the cylinder head design and the cam timing. The trick is to slow down the gasses exiting the combustion chamber so as not to promote charge transition. It’s another reason Ti headers are a great thing.

The fact that you can ride around without upsetting other people is an added benefit.

Pete

Pete Roper wrote:

It’s down to the cylinder head design and the cam timing. The trick is to slow down the gasses exiting the combustion chamber so as not to promote charge transition. It’s another reason Ti headers are a great thing.

The fact that you can ride around without upsetting other people is an added benefit.

Pete

Thanks Pete.

cognosticator wrote:

Pete Roper wrote:

You’ll find it runs better with the dB killer installed anyway.

I am wondering in what way it runs better.  I am running my GPR with the db killer out.  Thanks

This reply may plunge my ghetto cred into negative territory, but...

I expect your GPR would be similar to my open termi.

In 2011 after fitting the termi slip on I ran the GRiSO on the dyno with DB killer in and out.

Power and torque right through the rev range was higher with the DB killer out.

It was also smoother right through the range although the 3000-4000 range back in the day with the original mapping was all over the place anyway.

The 5500 rev power surge present under the original ecu mapping was more pronounced with the db killer in. Effectively a spike.

From 7000 revs to redline, the maxxed power curve stays flat until the rev limiter hits with the killer out.

With the DB killer in, the power curve drops significantly from its peak at 7200 as the poor bike at revs is being choked.

I call it the emphysema effect The bum on seat really notices the difference which is the crux of the biscuit.

Exactly as you'd expect when you restrict an exhaust.

Suffice to say the termi fitted GRiSO is not loud when compared to my 1098R with full 70mm termi system or the plague of hardly dawdlingsons that infest our streets.

Each to his own I say, but to be demonised for hooliganism on a bike whose very name be GRiSO, the thug, is a bit strange...

There is no need for a GRiSO to be noisy. I can hear mine just fine when I’m on the gas. When i’m Droning I can’t, it’s great, avoids fatigue. I have no desire to annoy others with my pastimes. Each to their own.

Restriction isn’t the aim but slowing down the exiting gasses is. Open pipes will encourage charge transition and lower VE in most of the range. They will move the maximum torque point further up the range and may give a smidgen more top end if mapped correctly but since that is really not much use apart from at a track day I’ll go for overall tractability throughout the range and lower fuel bills.

If I do want to go for *Maximum Whatever* I can always remove the dB killer and flick the ‘No dB Killer’ map into it. Thing is I never feel the need. (Shrug.)

Pete

That's a fair assumption.  But an assumption is a guess without evidence.

I first did this experiment because of claims in 2010 the GRiSO 'runs better' with the killer in. Even at low revs with the rough pre 068 map, it ran smoother and with more power with the killer out. Same with the 068.  I've not tested with the roller map because that's better still and I'm happy.

Yes, I follow this closely because I would rather have a quieter bike with the same or more power and will switch given evidence I've not seen yet.

Past evidence does not support it. Anecdote does.

So what map are you currently running? The last factory iteration?

Pete

Yes, the latest factory map. I would run after market proprietary maps like rexxer if I was not happy with the performance.

That would explain it then.

Look, if you’re happy? That’s great. Be warned though the Rexxer offerings are really pretty crude.

Pete

Would it be easier for someone to send me a photo and dimensions of a Termi DB killer?

Stubbie wrote:

Would it be easier for someone to send me a photo and dimensions of a Termi DB killer?

I flew in last night. It's at my Jandakot shed. I'll be there Tuesday. You can have it. I'm now convinced I won't need it

(where's the shit stir icon )