
Gt186 carb and exhaust
I have a gt186 with 25mm carb through air box and 42mm af clubman and on a garmin gps can get 70mph although sit at 60 most of the time as I only wanted a tourer, I don't bother with dyno as I don't think they help as its not the real world ie inside building, sidepanels off and when I have had them running sweet and dynode them in the past run s**t after so I just do plug checks through different speed ranges now, wouldn't have a clue on hp but then I don't care if its running sweet which it is
I ran a 25mm dellorto and a AF clubman on my GT 186 for about a 1000 miles all through the running in period and I liked it however I changed to a 30 mm and a MB clubman and now it's a transformed bike I've had a good dyno results but on the road she's a real wolf in sheeps clothing I've been clocked by the Mrs in the car doing just over a true 70mph and acceleration wise it's given a quite TS1s a run for their money it's full panel work as well
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I agree that the number is to some extent academic, but is a very good indicator as to whether you're in the right area or not. This is even more true of a gas analyser.yozzer wrote:I have a gt186 with 25mm carb through air box and 42mm af clubman and on a garmin gps can get 70mph although sit at 60 most of the time as I only wanted a tourer, I don't bother with dyno as I don't think they help as its not the real world ie inside building, sidepanels off and when I have had them running sweet and dynode them in the past run s**t after so I just do plug checks through different speed ranges now, wouldn't have a clue on hp but then I don't care if its running sweet which it is
Also some people (me included) don't know how to do plug chops with any degree of accuracy.
What I'm really asking about is the apparent chasm between my 10bhp bike and the 'norm' of 15ish from my set up.
I'm also perturbed by the extremely rich jets I have to get close to a good A/For ratio compared to rich Taylor's recommendations.
Something is wrong and it's the dyno and gas analyser that have told me.
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I tried a plug chop this afternoon (first one I've ever done). I did it at WOT after about half a mile uphill in 3rd gear. Here it is.

I have no idea what to read into this
To me it looks like the centre of the plug is perfect but that the edge of it is way too rich! Clearly this can't be the case. Can anyone help me out here?

I have no idea what to read into this

To me it looks like the centre of the plug is perfect but that the edge of it is way too rich! Clearly this can't be the case. Can anyone help me out here?
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The fundamental difference in your engine build is the ignition. I would really strongly suggest that you fit a borrowed Indian electronic and put the jetting back to original spec. Then give it a try
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I'm doing a leakdown check tomorrow morning (just to eliminate it from our enquiries) then I'm going to fixed ignition and original jetting. Because of course, it could be that I've built it badly.Rich_T wrote:The fundamental difference in your engine build is the ignition. I would really strongly suggest that you fit a borrowed Indian electronic and put the jetting back to original spec. Then give it a try
Thanks for your help.
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Considering buying this kit for my Eibar S2 as I'm very happy with the GT200 kit in my GT200.
Was going to run with a 25mm phbl through a drilled air box but could consider removing this and using remote filter. But what exhaust would people recommend? Was thing Franspeed race but I don't see an option for S2 with standard manifold, does anyone have any experience of a Super Tourer with this kit?
Rich you'll probably get an email from me over the next few days, but essentially I'm waiting for your new crank to become available and ordering all together. Are we still looking at August for these to be ready?
Was going to run with a 25mm phbl through a drilled air box but could consider removing this and using remote filter. But what exhaust would people recommend? Was thing Franspeed race but I don't see an option for S2 with standard manifold, does anyone have any experience of a Super Tourer with this kit?
Rich you'll probably get an email from me over the next few days, but essentially I'm waiting for your new crank to become available and ordering all together. Are we still looking at August for these to be ready?
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Just done a leakdown check. So this weekend I've done my first ever plug chop and first leakdown; how exciting!
Anyway, it's as airtight as a nun's chuff, so that's good.
I've taken Rich T's advice (I reckon he knows a thing or 2 about GT kits) and ordered a BGM stator and lightened af flywheel, so I'll see where I go from here.
Only problem now is that for a genuine quanitifiable comparison I need to go back to Ripon............
Anyway, it's as airtight as a nun's chuff, so that's good.
I've taken Rich T's advice (I reckon he knows a thing or 2 about GT kits) and ordered a BGM stator and lightened af flywheel, so I'll see where I go from here.
Only problem now is that for a genuine quanitifiable comparison I need to go back to Ripon............