GT200 with Malossi 218, 4v, cam, lv4road. No change?
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Hooked
GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Mon Dec 11, 2017 5:57 pm quote
Thanks for the reply Motovista.

That was what I was after. I didn't realise you could get the rocker cover off in-place and see the cam mark. I have a snake (Camera on a bendy stick with a light) which should take care of that. Phew. You did mention a mirror up the posts a bit, but there was "might" in the same sentence so I figured you hadn't tried it.

I really have cam timing still as the most likely cause, Ivo believes he has it right, but the flat out test contradicts that. Of course he would try to convince me it wasn't the cam timing because unless he was a total wanker he would believe he'd got it right. What I wasn't prepared to do was just go in there and say "It's wrong, fix it" without "knowing", in the absolute sense of the word, it's wrong and showing him. I've had enough experience with people telling me I've buggered something up on a hunch of theirs to require more evidence prior to wasting my labours, I wouldn't expect anything different from anyone else.

Sorry to be so touchy on the subject, but most of my life I've had to deal with people doing what you told me to do to someone else.

I'll pop the rocker cover and water pump off this afternoon. Despite my gnashing of teeth, I really hope the cam is out. In fact nothing would cheer me up more!

Thanks for the instructions, I'll post how I go.

Now calm down Caketin and get on with the job.
Hooked
GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Mon Dec 11, 2017 6:51 pm quote
"Rocker cover" lol, that shows my age. What rockers?.
Hooked
GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Tue Dec 12, 2017 2:22 am quote
That was hard and reminded me of why I sub this stuff out these days.

I didn't realise I would need to all but drop the engine to get the water pump off. I couldn't do that in the time available today, but I did crack a few of the screws that hold it on and judging by that "crack", they've been living in their alli housing since Italy, so no, Ivo didn't take that off. I hope loosening the top cylinder hose until coolant comes out is enough to re-prime the cooling system.

It was very difficult to find a timing mark even through the water pump sight hole. I did locate the 4v one on the cam sprocket, but without dropping the engine you need hands the size of a six year old girl just to get the valve cover off.

Luckily I have such hands.

When the 4v mark was lined up I couldn't see the timing mark through the water pump hole, but I never saw it anyway, even after sticking a cotton bud in there to clean it. I cranked the engine back and forth with the variator nut, but saw nothing.

At least all the bolts got a good coat of neverseize and I learned how to take a fair bit of it apart. The filter in the gearcase was rooted, I might just cut up the old air filter to make another one. I think I'll junk the air box and put a K&N pod on it.

So I'm not really much wiser, but having expended the energy I'll take it back in the next day or so and have Ivo strip it to the flywheel without feeling I took the easy way out, which is to complain without at least trying myself.

Thanks for the advice everyone.

I feel like I need a nanna nap.
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Tue Dec 12, 2017 3:21 am quote
Caketin wrote:
"Rocker cover" lol, that shows my age. What rockers?.
Rocker arms? Is there another word for them?
Hooked
GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Tue Dec 12, 2017 5:41 am quote
I think rocker arms are attached to Rockers, but not Punks or Mods. I'm confident they used them to punch Mods with, unjustly.
Hooked
GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Tue Dec 12, 2017 11:30 pm quote
Sorry, winding myself in knots, the last valve cover I took off had cams over the valves. Pushrods was what I was thinking of being a thing of the past, except in the U.S. of course.

Back on topic. I have taken the GT back to the shop and convinced them it's a tooth out. I'm hoping it is, and it makes more sense than any other explanation. I'm going to pop in when it's stripped. Fingers crossed.

One more thing that convinced me of the cam timing, is when I accelerated off a traffic light the other day the rear wheel actually let go on dry bitumen when the clutch grabbed. Low torque and no top end is a symptom of the cam shift. It's never done that before, I had to look about to make sure the squealing came from me.
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LXV 150 Midnight Blue (SOLD)
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Wed Dec 13, 2017 12:25 am quote
Bit of a Schottky to realize you are from Darlington where the transistors come from?
Veni, Vidi, Posti
LX190
Joined: 12 Oct 2007
Posts: 5495
Location: New Zealand
Wed Dec 13, 2017 12:38 am quote
waspmike wrote:
Bit of a Schottky to realize you are from Darlington where the transistors come from?
Where you can drive 800 miles without seeing a cop?
Hooked
GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Wed Dec 13, 2017 2:20 am quote
Ok, I give up. I've got no idea what your all on about, but it is true you "never" see cops in Darlington, except once about 4 years ago they set up a speed camera outside the primary school on the first day back, which is fair enough I supose.

I did belt the GT from Darlington to Mundaring (another nowhere place in WA) and caught up to a group of blokes on bikes. I had the baffle out of the LV at the time and was making a lot of noise and doubling the speed limit. Arriving in Mundaring (at the same speed) there was a cop with a speed cam. He didn't even point it at me, lol.

Just another advantage of scooters.
Hooked
GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Wed Dec 13, 2017 2:34 am quote
There are a lot of Darlington's in the world, maybe my little remote one in the Western Australian Perth hills isn't the one you're on about. It fits the bill though, the next capital city is 2600km away, and even the most irresponsible behaviour doesn't attract the law here.

Our "Darlington" is so named because a bloke called Darling "Discovered" (about 60,000 years after the Aboriginals did) a modest range of hills to the east of Perth. Being a town on the scarp of those hills we got christened Darlington in about 1895.

Luckily the roads into Darlington are pretty close to dead ends, so no-one tends to find us, including the plods, or a reasonable internet connection, sewerage, or services of any kind, etc. The posties can find us though thank god.
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Granturismo 218
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Wed Dec 13, 2017 7:51 am quote
Caketin wrote:
It was very difficult to find a timing mark even through the water pump sight hole. I did locate the 4v one on the cam sprocket, but without dropping the engine you need hands the size of a six year old girl just to get the valve cover off..

The timing mark that you see through the sight hole on the water pump is the ignition timing mark that will put you off a tooth. You can remove the water pump, without draining the coolant, etc, push it up and to the side and see the cam timing mark ON THE FLYWHEEL.

Bird.jpg

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GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Wed Dec 13, 2017 4:24 pm quote
Hi motavista, thanks for the triple face palm, you really do think the worst of people don't you?

You had already told me the mark through the water pump would put the cam a tooth out hadn't you? So, when I realised I was going to need to drop the engine to get the water pump off (or at least mostly drop it) and had neither the space or inclination to do that, it seemed like a good idea to check and see if the cam mark lined up with the water pump mark as that way I would "Know" the timing was out wouldn't I???

You really are hard to love.
Hooked
GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Wed Dec 13, 2017 6:22 pm quote
I also figured if the timing mark on the water pump was aligned or 2 teeth out that would tell me the timing was likely wrong, which is why I checked those positions too. I never found the mark though.

I never intended to reset the timing myself, just establish it was out before I had the Vespashop pull it apart. If I had gone to the trouble of dropping the engine I may as well have carried on and fixed it myself, but I wanted them to be responsible for that. If I'd buggered anything up doing it it would become my responsibility, this way it's theirs.

I did a 0-100kmh acceleration test and it was pretty much the same as stock, about 13-14 seconds. It's got to be the cam.
Hooked
GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Wed Dec 13, 2017 8:07 pm quote
Flattered as I am to be depicted as a Drongo bird, in Australia we tend to use the Galah,

1bd1062654708fe1468c1d6615121ee1--newborn-animals-newborns.jpg

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GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Wed Dec 13, 2017 11:50 pm quote
On the off chance I can post something without being ridiculed by Motovista, I'll put my head on the block and try again.

So I've just got back from the Vespashop and sadly the timing is perfect. The marks on the flywheel align as shown on p146 of the manual, as does the 4V mark on the cam sprocket.

Ivo and Roberto insisted on not charging for labour, but I counter insisted they do, so I'll be out of pocket a few bucks but at least I "know" it's not that.

Which gets us back to the beginning.

The first thing I will do next is to fit the tach I now have, then remove the airbox, test it, and fit a K&N pod. Depending on the rpm I get I should be able to work out what needs to happen with the variator. Using the multimeter and the hertz method I was finding it would bog down to 6500rpm WOT on occasions. That's way too low to get life out of the head/cam set up. I'm guessing there's a few pretty flat rollers in there as this doesn't always happen, sometimes it will hang on to 8000rpm. I suppose it depends where the rollers settle idling before the launch, on their flats or on a round bit.

I'm still confused why at full speed it was stuck at 120kmh, but if the airbox is the weak link (It has a very small inlet hole) that would make sense. I'm doubting it's the carb as at least in theory a 33mm should be good for 10,000rpm on a 218cc.
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LXV 150 Midnight Blue (SOLD)
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Hooked
GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Thu Dec 14, 2017 1:56 am quote
Thanks waspmike. I checked that out but they were a bit all over the place, which I suppose we all are when playing with engines we're not familiar with.

I was really surprised at the size of the inlet tube on the airbox, it looked smaller than the venturi! It may breath ok through it, but if it pulls up any sort of a vacuum it's going to suddenly richen the carb coming up to the flow needed.

I need to take a breath and work methodically through the possible restrictions. Breathing and rpm too low are easy to fix and don't cost much. If I fix one the other will become a problem so I may as well knock those on the head first.

Malossi wont have wasted their time with this package, so I know the horsepower is in there somewhere. I really did get an extraordinary pull up to 60kmh the time it ran to 8krpm, but then the variator sunk it. I've spent the big money, now it's just fiddling.

This test (in WA surprisingly) shows how much can be extracted with variator tuning and the right filter.

http://scootercommunity.com.au/forums/t/12927.aspx?PageIndex=1
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2014 Commuter BV350(37,000)/2015 Scoot Life BV350(9,000)/2010 El Diablito SH150i(28,000)
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Location: Orange Park Florida
Thu Dec 14, 2017 2:51 am quote
Here's a quote from your link that interested me.

"I passed similar modification and based on rich experience I can tell you that you wan't feel or measure any power, acceleration or speed increasement;-(
Since then I give-up and swapped engine for bev350ie"
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GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Thu Dec 14, 2017 5:51 am quote
Yep I read that, but if Malossi are to be trusted at all, in the case of a GT200 the torque and horsepower gains around the 7,500 to 10,000 mark are between 25 ad 33%. That should be a seat of the pants difference.
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LXV 150 Midnight Blue (SOLD)
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Thu Dec 14, 2017 5:35 pm quote
Caketin wrote:
I was really surprised at the size of the inlet tube on the airbox, it looked smaller than the venturi! It may breath ok through it, but if it pulls up any sort of a vacuum it's going to suddenly richen the carb coming up to the flow needed.

I need to take a breath and work methodically through the possible restrictions.

Have you looked at this?

http://modernvespa.com/forum/topic60894

It would seem to me that the airbox entry should be the same or bigger area than the outlet tube or the carburetor throat.

Variator? I'm a J Costa man but they are point and squirt British B road variators designed for roll-on/corner exit/ passing/ uphill performance. Not really for riding wide open for long periods on straight roads. Each to their own.
Mike Holland is your man. But I notice he hasn't posted on your dilemna.

Last edited by waspmike on Thu Dec 14, 2017 6:02 pm; edited 1 time in total
Hooked
GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Thu Dec 14, 2017 5:59 pm quote
Thanks waspmike. I agree the airbox does seem to be designed more to prevent the ingress of birds and animals than flow air, lol. I will put a pod on it. If you follow a puff of air through my bike the only restricted part is the airbox, I'm also partial to intake noise.

I wonder whether the one on the GTS 300 is internally the same? I suppose with fuel injection the engine would compensate for any restriction by leaning the mix.
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GTS300 Super Blue Gaiola
Joined: 01 Nov 2005
Posts: 2492
Location: Sydney, Australia
Thu Dec 14, 2017 6:06 pm quote
Sorry, Caketin, but I don't have much to offer. I fitted V4 kits to both my GTS250 and my GTS300 (same head moved along), but never to my GT200. I had a Costa variator on my GT200 which gave excellent results. I think it was better than the Polini that I installed on the 250 and 300.

I fitted a slightly larger main jet to the carb of the GT200 with good results, but can't recall the size. About 4 or 5 sizes larger.

When I have fiddled with the head and cam, I have just viewed the timing mark through the plug hole to get TDC, but I have generally done this with the engine out on my workbench, so didn't need a mirror, but a torch still helped. I also checked with a probe through the sparkplug hole. Always worked for me. But that mark on the flywheel is very difficult to see.

Wish I could be more use.

Mike
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LXV 150 Midnight Blue (SOLD)
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Thu Dec 14, 2017 6:08 pm quote
Caketin wrote:
I'm also partial to intake noise.
https://www.youtube.com/watch?v=HgaXIkOnlVQ

Spot the FIAT(s)?
Hooked
GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Thu Dec 14, 2017 11:23 pm quote
ha ha, lots of growly induction there wasp.

Speaking of which (And thanks Mike Holland for joining in) removing the air box and fitting a pod, or even leaving the carb open, I have about 1/8th throttle before it bogs into a choke, total choke and dies that is. It should be lean of course, but surely the air box isn't so restrictive it puts it so out of tune without it it won't run past 1/8th throttle? It felt like it was rich but that made no sense at all. I dropped the needle back to the centre position to see what affect it had and if possible it got even worse! 1/16th throttle!!.

Changing the main jet is easy as I have heaps of them (Now!!!), but in this range it's not really got much to do with the main jet. Either way I'm going to pop in the 110 (original was 95, currently 100 fitted) just to give me some parameters to start working with.
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GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Fri Dec 15, 2017 12:28 am quote
Right, so since my last post I've put in a 110 main jet - tiny bit better but totally bogs past 1/4 throttle still, the original 95 main jet - worst of all, and now I'm sitting next to it with a gin and tonic wondering what's next. With all of these jets it will take throttle through the range with the air box on, but it just isn't pulling. With it off it dies to the point of not firing at all after 1/4 throttle.

I had thoroughly cleaned the carb prior to installing the kit and it was performing normally. After the kit, and with the airbox on it was about the same as before it, but felt like it was suffering from starvation. The fuel pump work fine, as the hoses where cracked when I got it out of mothballs and healthy jets of fuel were spurting out of the cracks.
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GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Fri Dec 15, 2017 1:45 am quote
Back to the needle raised a notch and 105 main (+9%), which I think should have been close.

Significant fuel starvation after 1 - 1.5sec WOT, but not immediately. It's not long enough to drain the float bowl, but maybe enough to lower the level and lean it out if it has a supply problem. This doesn't happen with the air box attached, but it does feel lean then too and wont go.

I can crimp the airline from the inlet manifold to the fuel pump and affect the idle (I don't think I should be able to), but it's a bigger problem than that. Even on the stand I can shut it down with WOT. No jetting or needle positions make enough difference to be close. Only the air box.

What is the chance a weak spark could cause this do you reckon? It makes no sense to me.
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Fri Dec 15, 2017 2:36 am quote
Right, just seen your results of checking the cam timing. That's very interesting and I'd have eaten my hat that it was off a tooth as frankly that's often what you find in this situation. Well done for checking it out and sorry that wasn't the problem.

In a situation like this I normally pop it on the dyno and do some tests but you clearly don't have the option. So it's a case of working it through, very much like you are doing and checking out individual scenarios. And it would have to run well enough to go on the dyno anyway.

Regarding the 'spark' thing you mention. Yes, sparks can affect it and could be a cause. It could be the plug or the cdi unit. Did you replace the plug. If the old plug was borderline the increased compression of the conversion will increase resistance on the plug firing. As you open the throttle, under load, it will get worse causing lack of power and or misfiring. Of course, your observation of suspected fuel starvation either due too to little fuel being pumped or air starvation will be just as valid and maybe more so. At this point I would be checking out every hose, fuel or air, for damage & blockage, replace the spark plug (if not already done), check the spark plug lead for integrity and replace if in doubt, and check fuel pump filter for partial blockage. Even with the standard airbox/filter it should still run reasonably ok in my experience and deliver more power than standard. If at the moment you have removed the airfilter that will of course make it run lean and make any existing fuel starvation problem worse as it will just suck more air. I'm going to review what you have done and see if I can offer anything else. Wish I could see the bike. It's solvable so don't despair. It'll be something simple, usually is!
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GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Fri Dec 15, 2017 2:52 am quote
Thanks Stormrider.

I changed the plug twice, just to be sure as it's cheap. It's an NGKCR9EB

Part of the reason I removed the air box was to exaggerate any leaning out problem if that was the cause. I certainly didn't expect it to die at 1/4 throttle, but that's actually good news as it means it was just on the edge of running before. Fuel filter and all fuel lines were replaced a few weeks back, but not the pulse lines from the manifold.

A 4 stroke will put up with a pretty wide range of fuel mixtures so it must be out by a shit load to die at 1/4. Funnily enough, I'm happy about it, because if the performance I was getting was all Malossi had to offer I would have been a bit disappointed.
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GTS300 Super Blue Gaiola
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Posts: 2492
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Fri Dec 15, 2017 3:26 am quote
I never got the hang of CV carbs, but I would be checking the diaphragm for not seating correctly, or being damaged.
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GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Fri Dec 15, 2017 5:40 am quote
Yep agreed, but I've changed the needle position so often just today that it's unlikely I've missed any holes or got the seating wrong everytime.

This isn't a subtle problem, it's out by 50%. Most 4 strokes will at least run with anything from a 7:1 to 18:1 fuel mix, mine won't run beyond 1/4 throttle, it's waaaaay out.

It ran with the airbox, but I'm guessing it only just did, which is why I thought the cam was out. This is one of those problems that when it is solved it will have cost nothing and go like the clappers. To get from there to here needs a flash of inspiration.

Where is Motovista when there's no ridicule to be had? Go on, just offer some advice without taking the piss...you know you can do it .
Molto Verboso
2016 Vespa GTS300ie abs/asr/ess Settantesimo '70'
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Location: Not really sure but I think somewhere in the engineering dept at Starfleet's UK HQ
Fri Dec 15, 2017 9:46 am quote
Caketin, just a thought before going any further. Is your petcock a vacuum operated one. I thing it is on the GT200. If so, make sure the diaphram isn't damaged. If it is you may starve of fuel when you open her up on the throttle. Is the line to the inlet manifold leaking at the manifold. If so it won't deliver fuel properly. Just confirm those are ok please.
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LXV 150 Midnight Blue (SOLD)
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Fri Dec 15, 2017 4:38 pm quote
There are many websites to help with carb tuning.

Here are the basics http://amalcarb.co.uk/downloadfiles/amal/amal_tuning_guide.pdf

CV carbs are a tad different as the slide cut-out varies with butterfly opening but...

Noting that all methods for all carbs. start with getting the main jet correct, maybe look somewhere else if the bike won't run beyond 1/4 throttle.
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GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Fri Dec 15, 2017 8:12 pm quote
Split under the intlet manifold!

When the airbox was on it pulled it closed, when off the hoses opened it up.

Jeez-Louise.

It might have opened up back when I first pulled off the carb to clean it a few months ago, but the leanout became more obvious with the Malossi kit, and finally barking in my face when the filter box was off.
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LX190
Joined: 12 Oct 2007
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Fri Dec 15, 2017 11:38 pm quote
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GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Fri Dec 15, 2017 11:58 pm quote
Thanks znomit, but far from applauding myself I feel like taking to it with the block splitter.

When the last few pieces are pounded to dust I "might" start feeling better.
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LX190
Joined: 12 Oct 2007
Posts: 5495
Location: New Zealand
Sat Dec 16, 2017 12:13 am quote
You’ll feel better after your first wheelie.
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GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Sat Dec 16, 2017 12:21 am quote
Yes, I will..
Molto Verboso
2016 Vespa GTS300ie abs/asr/ess Settantesimo '70'
Joined: 11 Jun 2011
Posts: 1744
Location: Not really sure but I think somewhere in the engineering dept at Starfleet's UK HQ
Sat Dec 16, 2017 9:22 am quote
Ok, that's great you've found the problem! Illustrates how awkward internet diagnosis can be...lol. That bike should fly once you've fixed it. Good luck and post back with your thoughts when you have had a decent ride! Bye for now.
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LXV 150 Midnight Blue (SOLD)
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Sat Dec 16, 2017 4:13 pm quote
Stromrider wrote:
Illustrates how impossible internet diagnosis can be...lol.
Sorted that for you.

It does show that usually it is a simple thing not some corporate conspiracy.

I don't mind as long as a I learn something. Although this time I still don't know what any of the cam timings are.
Hooked
GT200
Joined: 12 Nov 2017
Posts: 112
Location: Darlington Western Australia
Sat Dec 16, 2017 7:19 pm quote
Hi waspmike,

referring to something you said earlier about the JCosta variator, my riding style is very much the "B" roads rather than flat out. Here in the Perth hills most roads either go steeply up, steeply down, or around tight corners, so what you are describing sound fine. The only niggling doubt I have is there isn't much in the way of weight choices for the JCosta, so though the lads at the Vespashop like them more than the Malossi, they were concerned I'd get trapped in the wrong rev range with the new set up.

I have installed a tach on mine now, but the readings aren't of any use with a holy manifold. Even so, it was all over the place. I did the same short ride twice (before I discovered the hole, but without touching anything in between them) once hit 8500rpm max, and the next time 7200? I'll need a lot more consistency that that. 8500 is perfect for a thrash. Have you ever had a tach on yours?

Cheers,

Cake.
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