V65C carb tuning |
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cyclobutch
Senior Member Joined: 08 Sep 2015 Location: Essex Branch Status: Offline Points: 750 |
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Some more observations from my side:
I originally pulled a head when the motor was
at maybe around 25k miles. My reasoning for this was that I’d stored the bike
over winter and in the spring when I turned the motor over, one of the valves
was stuck down and the piston touched it. Hence I decided to swap that out.
When I pulled the head I found a large area – maybe the size of a half crown
(can’t think of a modern equivalent; bit bigger than a 50p ?) of Nikasil missing
from the bore. So along with a new valve – the original didn’t look damaged but
just to be sure; I ended up fitting a
new barrel and piston. Upon which basis I decided to pull the other side for a
look - and that was when I found that rear head to barrel bolt seized, and tore
the socket out in it. I figured I didn’t need to look in there that badly.
I pulled the heads again at 48k miles to swap
out all of the valves due to their reputation for dropping at that kind of
mileage. I understand that they are a two piece – stem and head, that are
swaged together; and that they will stretch and break (how do you tell the
difference from the outside between valve stretch and seat recession?). That
was when I had to angle grind that bolt head off. Nikasil on both side was
fine.
At 55k miles I found that the engine was ‘breathing’
heavier and heavier amounts of oil, which I figured was crankcase
pressurisation due to worn rings. I fitted a catch bottle for a year or two.
Did a compression test and it was pretty good, bike was still running fine. I
eventually pulled the heads again to re-ring when I started using the bike more.
Rings were worn, and oddly they were worse on the ‘new’ barrel side,
particularly the oil scraper. Rings were a slightly different design though.
Bores on both cylinders were perfect – as in you could still see the hatching
markings. I was concerned over roughing up the Nikasil to get the new rings to
bed in, and on advice didn’t do that.
My engine is quite noisy – tinkly in the top
end (I don’t mean pinking), but I purposely didn’t check my little ends as
there was no way I was prepared to commit to a full build that would inevitably
result in further inspection and al new shells in the bottom end. So best not
to know. Also, Is couldn’t be bothered to pull out and regrind the valves at
that time. New rings fixed my issue OK. I’m at 62k miles now and the bike still
runs strong if a little rattily (or do I mean rattley?) – and I’m still happy
to buzz her along at 70-80 per where conditions allow. I helped my pal
recommission his <30k mile V50 a couple of years back and mine is
appreciably a lot noisier than that.
Not sure how that helps, but there it is. |
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Butch
V50 II - 'The Black Pearl' T3 - 'Blue' Eldo Loop - 'Jug' |
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Mike H
Senior Member Joined: 21 May 2014 Location: East Anglia Status: Offline Points: 8733 |
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Very interesting! Not the same I know but my 850 Tonti was blowing oil, also due to pressurization I believe, OK if I kept the throttle and revs low, but became useless for too much motorway type speeds. Same sort of mileage too, well more like 65k in fact. Lots of 'top end' noise too. Got the arse with it in the end Ray Dunkley's got it now.
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"Chicken nuggets don't dance on a Tuesday."
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Jim
Senior Member Joined: 04 Oct 2015 Location: Rome Status: Offline Points: 111 |
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Well, it sounds like taking the heads off is a regular necessity.
I would only add that last time (many moons ago) I also changed the big ends. I'm glad I did have a look cos. they were all scratched up. I have to admit I didn't want to take the whole lot apart for the same reasons as Butch (fearing can of worms) so I got the bolts off the big ends through the sump. The naughty thing was doing them up again. I couldn't get the torque wrench on 2 of them (only on one nut of each con-rod). So I did them up a bit at time together, gauging the force to apply by comparing with the one I could get a reading on (and using the same lever i.e. torque - feel with a spanner - tighten the other nut the same). Does that make sense? This is not recommendable but it worked for me and I have no intention of taking them apart to look at them again this time! Oh for more time to spend in the shed checking a few more bits. Then I must get my order done. I need a new bathroom too cos. it's leaking and that's a priority unfortunately (apparently ). I don't give up though. |
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cyclobutch
Senior Member Joined: 08 Sep 2015 Location: Essex Branch Status: Offline Points: 750 |
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Ah – shed time. I’ve currently got my ‘Beam up
on the table in the garage, engine out for a new clutch, and a few other bits.
Should go back in this weekend. Then I’ve got my ‘new’ lathe (1921 I’m told) to
install down one sided along with wiring some new strip lights. Then Blue the
T3 goes up for work at the back end – usual drive line inspection, new shocks
and
make up a new loom for the rear lights. After
which the Board Tracker Bantam goes back up for wiring and an attempt to make
it run in its new format. Meanwhile the garden is a wilderness and my front room down stairs is a tip – waiting to be cleared and then decorated. At least whilst I’m in the garage I can’t hear the nagging. So good luck with all that. |
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Butch
V50 II - 'The Black Pearl' T3 - 'Blue' Eldo Loop - 'Jug' |
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Mike H
Senior Member Joined: 21 May 2014 Location: East Anglia Status: Offline Points: 8733 |
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LOL ...
Reminds me of... |
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"Chicken nuggets don't dance on a Tuesday."
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italianmotor
Senior Member Joined: 14 May 2014 Location: UK Status: Offline Points: 2101 |
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"Hey, Tommy, you're a funny guy!"
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Guzzi lover doing my own thing: http://www.italianmotormagazine.com
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cyclobutch
Senior Member Joined: 08 Sep 2015 Location: Essex Branch Status: Offline Points: 750 |
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So Jim - is this all working and fixed and lovely and smashing now?
... to tell you the truth, in all this excitement I kind of lost track myself
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Butch
V50 II - 'The Black Pearl' T3 - 'Blue' Eldo Loop - 'Jug' |
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Jim
Senior Member Joined: 04 Oct 2015 Location: Rome Status: Offline Points: 111 |
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Hi folks,
just to say I've been ill, been to the UK and had my pc stolen So that's why I've been off the radar for a bit. I did manage to order gaskets etc. nearly 2 weeks ago but they haven't arrived yet. I will keep up this thread when there's news. Bye. |
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johnno
Senior Member Joined: 19 Jul 2014 Location: loughborough uk Status: Offline Points: 5582 |
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Hi Jim hope you and bike sorted soon
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1100 sport corsa , Yam R1, guzzi 650tt rider
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Motty
Senior Member Joined: 03 Jun 2015 Location: South England Status: Offline Points: 269 |
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Talk about things going from bad to worse, I hope life stops kicking you in the teeth and things improve |
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It’s more fun to try to ride a slow bike fast .....
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Jim
Senior Member Joined: 04 Oct 2015 Location: Rome Status: Offline Points: 111 |
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Just to say I'm still here (and still on my Honda XL 125 instead of the V65C). The bits arrived to rebuild the top ends and I started the job but today I over-tightened an oil scraper in the vice, despite wooden face-blocks, while filing it to fit and busted it. I've ordered another set but I'll have to wait....
The new ring sizes perplexed me somewhat and so I've opened a new thread on that too (while waiting for the new set). Jim. |
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exsmokingbiker
Senior Member Joined: 14 May 2014 Location: Blaby Leicester Status: Offline Points: 981 |
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and i still not sure what to do with it
the prices i have for lemans bits is halting it at the moment
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For all your engineering- ultrasonic and aquablasting needs see WWW.bike-aquablasting.co.uk
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BH Guzzi V65
Guzzino Joined: 25 Jan 2018 Location: Australia Status: Offline Points: 1 |
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I note you have a non-standard air-box, yours being an upmarket system. One of my friends had a Japanese bike with similar issues, could not get it to run properly. Changed back to the standard air box & voila, all worked perfectly.
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Bernie
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Jim
Senior Member Joined: 04 Oct 2015 Location: Rome Status: Offline Points: 111 |
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Hi, in the end I got a mechanic to sort it. He set the timing on one side to 10 degerees BTDC and the ther one to something crazy like 25!!!! But it runs OK. He said it was the best it could be with cone air filters and nearly straight-through pipes.
I think the only thing I did, apart from setting everything I could to standard (which was evidently not the right thing to do) was to file down the cut-awy on the throttle slides to help with the phase just after tickover. I changed needles too but I don't think it was very sensitive to the length of the conical part really. What a headache! |
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iansoady
Senior Member Joined: 23 Jul 2017 Location: Redditch Status: Offline Points: 2402 |
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I can't believe those timing figures!
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Ian
1952 Norton ES2 1986 Honda XBR500 1958-ish Greeves/Triumph in progress |
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