BIMOTA GT1 Project

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wolfgangh
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Re: BIMOTA GT1 Project

Post by wolfgangh »

Do you think it might help / do not do any harm to the engine if I reduce the ID of the holed tube in the muffler from 27mm to something smaller? This would create more volume for packing material - my concern only is that the engine might get too hot due to backpressure from the smaller tube acting as a vent.
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Suzukidave
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Re: BIMOTA GT1 Project

Post by Suzukidave »

I believe the stinger opening should be close to 1" (26mm ) - a couple of mm shouldnt hurt . You could remove the stock silencers and put on some that have more packing .
the older i get the faster i was
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smokin_blue
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Re: BIMOTA GT1 Project

Post by smokin_blue »

I would not go any smaller on the stinger diameter. You won't gain enough volume to have an effect. I would go with the other suggestions of remove the cans and replace them with larger diameter ones to allow more packing. The other thing would be to review what packing they have if any. Depending on the design they might not have any packing in there or it may not be that effective. I would start there and then increase can diameter only if you need to.
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wolfgangh
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Re: BIMOTA GT1 Project

Post by wolfgangh »

Here are pictures of the muffler internals- The damping material is only 5mm thick and 200mm long. I think I may go with larger OD and longer end piece to increase the volume of the muffler.

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Suzukidave
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Re: BIMOTA GT1 Project

Post by Suzukidave »

Jemco didnt do too sporty a job wrapping those silencers huh :shock:
the older i get the faster i was
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Alan H
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Re: BIMOTA GT1 Project

Post by Alan H »

Better to use stainless wire to hold the baffle wadding. When the tape melts it will start to move where it wants, and exhaust can't get through tape in any case, so the wadding can't work very well.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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Re: BIMOTA GT1 Project

Post by old racer »

That is not even baffle material It's glass fibre matting for layup.
Along with that tape wrapped around it i doubt it's doing much to silence it.
wolfgangh
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Re: BIMOTA GT1 Project

Post by wolfgangh »

Today Uschi, my gridgirl, came visiting me. Rolled the bike out of the workshop ad did a few heat cycles again.
One of the small M8 cylinder head bolts is leaking coolant, need to get a copper washer. The JEMCO´s are badly leaking at the flange, I am planning to weld on solid flanges to fix this oil leaking once and forever.

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simmons1
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Re: BIMOTA GT1 Project

Post by simmons1 »

Looks awesome!

What are you using for carbs, and do you plan on using the oil pump?

Thanks!

Rich
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Alan H
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Re: BIMOTA GT1 Project

Post by Alan H »

That's the best kind of woman. never talks back!
She looks a little bit, er, cold though. :wth: :shock:
Think of how stupid the average person is, then realise that half of them are more stupid than that.
wolfgangh
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Re: BIMOTA GT1 Project

Post by wolfgangh »

Hello Rich, these are Mikuni VM34 carbs and yes, I will use the oil pump. Its not going to be a track bike, I want to use it for sunday morning rides and some club gatherings, shows etc..and dont want to mess around with oil / gas mixing.
My pil pump is currently leaking, I ordered the gasket and seal to rebuild it. For the heat cYcles, I currently run 1:30 premix

Have also ordered a set of RAMAIR filters, both cylindrical ones and oval ones. Will see which ones fit better.
simmons1
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Re: BIMOTA GT1 Project

Post by simmons1 »

Thank you!

I would like to get rid of the CV carbs, once I get my cooling system issue fixed.
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tz375
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Re: BIMOTA GT1 Project

Post by tz375 »

34mm carbs will make more power, but CV carbs are better than you might imagine. Mine has run 12.8 quarter miles at 111mph with stock CV carbs and Bob Prior in the land downunder has run faster than that on CV carbs too.

For top end though and looks, VM34 or larger are better
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Suzukidave
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Re: BIMOTA GT1 Project

Post by Suzukidave »

I am pretty sure the head gasket should stop any coolant leakage around all the head bolts . Re torque maybe ?
the older i get the faster i was
simmons1
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Re: BIMOTA GT1 Project

Post by simmons1 »

Suzukidave wrote:I am pretty sure the head gasket should stop any coolant leakage around all the head bolts . Re torque maybe ?
Wrong thread but I already retorque the head.
T700, Africa Twin, Goldwing, Super Tenere, WR250R, GS1000s, GT750, H2 750
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