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Re: BIMOTA GT1 Project

Posted: Mon Apr 17, 2017 9:19 pm
by Suzukidave
Somethings wrong then as it shouldnt leak around the M8 head bolts .

Re: BIMOTA GT1 Project

Posted: Tue Apr 18, 2017 12:34 am
by tz375
Unless it's that stud with a nut on it close to the thermostat housing....... :?

On some barrels, that stud thread is open at the bottom to water and it will leak past the threads.

Re: BIMOTA GT1 Proje

Posted: Tue Apr 18, 2017 6:01 am
by wolfgangh
It is actually the M8 bolt between cyl #1 and #2. I noticed it jad been helicoiled by the PO, and now I assume he had drilled a bit too deep and that thread now is open to the water pocket below. That would explain why the thread of this bolt was wet with coolant when I removed it.

Can anyone confirm if there is a water pocket below the thread of this bolt in the middle of the head, between cyl #1 and #2?

Re: BIMOTA GT1 Project

Posted: Tue Apr 18, 2017 8:02 am
by tz375
Yes, that one will open into the water passage if it is drilled through. That should have a stud in it and not a bolt.

It might be better to drain the block and dry it and use epoxy to seal the bottom of that hole. You will have to create a bund or cover from tape or similar to hold it in place as it dries.

Or maybe try teflon tape around the threads to fill the gap

Or Three bond around the threads and under the head of that bolt, with a copper washer to help to seal it.

Re: BIMOTA GT1 Project

Posted: Tue Apr 18, 2017 11:43 am
by wolfgangh
This is the location of the leaking bolt and yes, the thread is definitely open to the coolant pocket. Easy fix!

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Re: BIMOTA GT1 Project

Posted: Sun Jun 25, 2017 1:19 pm
by wolfgangh
few new pictures - I have welded solid flanges to the JEMCO headers to stop the oil leaking; I have ordered another set of JEMCOs - without the integrated silencers - and will build my own silencers onto it, with 70mm diameter and 50mm longer, and the stinger pipe into the reflector. I hope to get noise down a bit with these modifications.

Note the syringe, which acts as my provisional oil tank, and the former coolant reservoir fixed to the steering head as my tank...

What do you think about the mirrors - are they too short, do you think longer ones would look better?

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Re: BIMOTA GT1 Project

Posted: Mon Jun 26, 2017 3:38 pm
by Alan H
Looking good.
If you think the mirrors are ok, then they're ok.
Just make sure they are useful for seeing behind you and not just your elbows!
Personally, I like bar end mirrors on low/flat bars, but not everyone else does.

Re: BIMOTA GT1 Project

Posted: Sat Dec 23, 2017 1:16 pm
by wolfgangh
Here is an update after a while. Picked up bodywork from the painters yesterday - exactly as I expected it. I had already installed a set of JEMCOs, but they are way too loud for use on public roads on my side of the globe. So I ordered a second set, without silencers, and will put on my own larger diameter and 2 inches longer silencers with different internals (diffusion and absorption portion) as well as an internal stinger into the belly.
Also need to fix an issue with my electronic regulator/rectifier - voltage goes up to 15,7V max which will kill the LiFePo4 battery I am afraid. Dont understand why this brandnew regulator behaves like this - may try the old original mechanical one.

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Re: BIMOTA GT1 Project

Posted: Sat Dec 23, 2017 2:34 pm
by Alan H
The usual cause of high charging voltage is low voltage at the regulator. Usually caused by a bad connection between battery and reg on the feed (control) side or even a poor earth on the reg will have the same effect. That makes the reg 'think' that the battery voltage is low, so it tries to put more into it to bring the voltage up to 14.2 ish. If you can't get this sorted easily or you are using a new 'thin wire' harness, run a fused wire direct from the battery + to the regulator via a relay that switches when the ignition is turned on and off.

Re: BIMOTA GT1 Project

Posted: Tue Dec 26, 2017 3:31 pm
by sportston
OMFG. I think i just had an orgasm! That bike looks super gorgeous. I don't think I've ever been this jealous before. That is probably the sexiest replica I have ever had the pleasure of seeing. :up: :clap: What does it ride like?

Re: BIMOTA GT1 Project

Posted: Wed Dec 27, 2017 3:02 am
by wolfgangh
sportston wrote:OMFG. I think i just had an orgasm! That bike looks super gorgeous. I don't think I've ever been this jealous before. That is probably the sexiest replica I have ever had the pleasure of seeing. :up: :clap: What does it ride like?
Hello Sportston,
It is not ready to ride yet, it is just a quick mock-up after I got the bodyparts from the paintshop. I am thinking of having the tank coated with some sealer (?) - it is an epoxy tank, I need to finish some electrics, and have bungs welded into the headers of the pipes for EGT sensors. Also planning to have both sets of exhausts ceramic coated in satin black.
The bike should roughly be 30kg lighter than stock, more weight could be saved with VM 5-spoke wheels which look exactly like the CAMPAGNOLOs of that period. I currently use KAWASAKI Z1000 wheels which weigh a ton each....

I won´t ride this bike a lot, there is no way I can get it street legal here in Austria. It will be reduced to some bike meetings on race tracks, or some short rides on hidden roads in the middle of nowhere.

I am very touched about the great feedback I am receiving from everywhere. This is not my first project bike, I have done some other two stroke customs already and few full restorations. I have a bone stock GT750A as well which I restored in 1999.

Here are some more pics:

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Re: BIMOTA GT1 Project

Posted: Wed Dec 27, 2017 12:28 pm
by wolfgangh
Alan H wrote:The usual cause of high charging voltage is low voltage at the regulator. Usually caused by a bad connection between battery and reg on the feed (control) side or even a poor earth on the reg will have the same effect. That makes the reg 'think' that the battery voltage is low, so it tries to put more into it to bring the voltage up to 14.2 ish. If you can't get this sorted easily or you are using a new 'thin wire' harness, run a fused wire direct from the battery + to the regulator via a relay that switches when the ignition is turned on and off.
Hi Alan,
thanks for your advice. I actually paid attention to that when I designed the wiring loom. My ignition switch is very close to the battery and the regulator to keep distances as short as possible. I measured the voltages today - I had 12,98V directly at the battery and 12,85V on the orange feed control wire going into the regulator. I dont think this causes the problem, I rather think the regulator itself is adjusted poorly. I will try another one.

Re: BIMOTA GT1 Project

Posted: Thu Dec 28, 2017 5:33 am
by rngdng
WE ARE NOT WORTHY!!!!!! AWESOME. I hope you don't have a problem with exhaust cracking as they are mounted. Everything look fantastic.



Lane

Re: BIMOTA GT1 Project

Posted: Thu Dec 28, 2017 12:22 pm
by wolfgangh
rngdng wrote:WE ARE NOT WORTHY!!!!!! AWESOME. I hope you don't have a problem with exhaust cracking as they are mounted. Everything look fantastic.



Lane
Hi Lane, thanks for the nice feedback. I am aware of the potential risk of exhaust cracking, I will do my best to add sufficient flex in the rear rubber mounts. I just cant stand those ever oil leaking spring mounted race pipes, it is just not adequate for this project. It needs to be clean.

Re: BIMOTA GT1 Project

Posted: Fri Dec 29, 2017 12:06 pm
by sportston
wolfgangh wrote: I just cant stand those ever oil leaking spring mounted race pipes, it is just not adequate for this project. It needs to be clean.
Here, here! I find it hard to understand how you can get consistent back pressure when they are always leaking.
I am quite concerned that you won't be able to ride the bike on the road in Austria. Have you considered putting your baby up for a foreign adoption?
It wouldn't be too difficult to get it road registered in the UK..... :up: if you required financial recompense I could always sell my wife or rob a bank. :ssh: