Guzzi07

Hi everyone: I am still playing with the Keihin FCR carbs on my 1995 Sport 1100, and would like to describe the issues I am still having and any opinions whether it is due to a too rich / lean condition. I think I know what adjustment I should make but want a second opinion. The issues are: 1. When the bike gets really hot in traffic (it is summer now in Aust) it develops a big flat spot off idle when the throttle is openned a little harder than normal, it misses / bogs down for a few seconds before taking off. This can be a little hairy when lane cutting in traffic! 2. The idle speed increases as the bike gets hotter. It goes from 1000 / 1100 up to 1500RPM. 3. On a trailing throttle just off idle, it misses sometimes. Thanks, Jason

I think the 60mpg you calculated is based on the British (Imperial) MPG (1 gal = 4.55 litres). A US gallon = 3.79 litres. Based on this, the highway leg equates to 4.65 litres per 100km = 51mpg (US) (60mpg imperial) and country riding 5.47 litres per 100km = 43mpg (US) (52mpg imperial). Conversion at: http://www.thecalculatorsite.com/conversions/fuelconsumption.php Overall this does not appear to be too far off, given my bike has different carbs.

Thanks for the info Mike Based on your figures I think the fuel economy is a bit too good (ie. low fuel consumption) and the bike is too lean. My MG 1200 Sport used to get around 5 litres per 100km on the highway with lean factory mapping (before I did a ECU remap anyway), so I was thinking that to get better than that with this bike might indicate a too lean mixture. I will keep monitoring the fuel consumption over the next month or so then start richening the slow fuel circuit to see whether I can reduce the flat spot between 1 & 2k rpm, and see if these changes makes much difference to the fuel consumption. Jason

Hi everyone: I have my bike back on the road now after a gearbox internals swap, new clutch, full service and working on the bike's Keihin FCR jetting. I have attached a few photos below. I am still fiddling around with the jetting and would like to ask what sort of fuel consumption people are getting from their Sports? I checked and on the highway run (averaging around 100km/hr - 60mph) I was getting 4.65 litres / 100km and 5.47 litres / 100kms in more hilly / backroad riding. I think the bike is still running too lean in the slow fuel jet area and the fuel consumption looks a bit low to me, would be interested to know what other owners get. Thanks, Jason

My problems were really related to some idiot in the past bolting on a set of FCRs to the bike without setting up the jetting. I think if you buy a proper kit, they really should just be a bolt on arrangement. After having worked on the carbs for a while (and learning a lot), I really began to appreciate they are a beautiful bit of engineering. From what I understand the ram air effect only really comes in to play above 160km/hr, unless you are going racing, I don't think the missing ram air setup will make much difference on the road. To my way of thinking, you actually should have no problems at all buying a standard FCR41 kit for the Sport 1100 with pod filters. The pod filters may flow a bit better, so you might need to richen things up a little. My setup is a bit of a problem as I am running a pressurised airbox without pressurising the float bowls, given you will not be using a pressurised airbox and just running the float bowls at atmospheric pressure, it should not be much of an issue (apart from the slight loss of top end performance without the ram air setup and maybe a little leanness due to the higher flowing pod filters). GuzziMoto seems to know a lot about these carbs, so hopefully he might add some advice. Having pod filters makes it much easier to work on the carbs and make preload adjustments to the rear shock (as well as sounding great), however at this stage I don't want to spend any money on the bike. Haven't played with suspension yet, plan to ride the bike over the Australian summer and then start working on the front forks next winter. I live in Canberra but have been working on the bike at my parent's place in Sydney. I plan to take the bike for a long run up the putty road on a weekend in late September / early October before taking the bike to Canberra, if you wanted to join me and have a look at the setup. Let me know via a PM if you want to meet up. Jason

I should have been a bit clearer, the carbs do not have male "nipple" vents (that I was expecting to find), however the carbs do of course have float bowl vents (I blew the vents out with compressed air when I cleaned each carb). The FCR link you provided is quite different from my carbs (though the basic workings are the same), this exploded view shows the design of my FCR39s: http://www.showandgo.com.au/carbie/fcrexp.htm Looking at it more carefully, I now realise that male pipes are all that is needed, they are inserted into the receptacle holes, with a rubber hose then used to connect the vents to the airbox. As I recall both ends of the vents are open, so I guess a rubber bung would be needed to block one end from atmospheric pressure. There would however be a problem with the R/H carb as some idiot has managed to break the round part off the vent receptacle casting (how someone would do this I don't know), though I could probably use some Devcon F to build up this receptacle again. In the end, even if I had looked a bit deeper and worked this out, with the broken receptacle on the R/H carb it would be too much hassle to setup for moderate gains at the top end of the range. If I eventually go to a proper FCR41 kit, I'll make sure I set up the pressurised float bowls properly. I plan to take a few pics of the bike when I pick it up in a few weeks (next to my 1200 Sport), I'll take a close up of the R/H carb with the broken vent receptacle. Apart from the carbs and someone using red locktite on the drive shaft clamps (the bolts were an absolute b**tard to remove), the rest of the bike is in great condition with no evidence that anyone has mucked around with it (i.e. missing parts, incorrectly assembled bits, stripped threads etc).

There are no nipples on the carbs to pressurise the float bowls unfortunately. There appears to be a type of FCR for bikes with pressurised air boxes (Kawasaki ZXR, Guzzi Sport 1100 etc) which has a vent nipple for the float bowl (just like the original 40mm dellortos that would have originally come with the bike) which can then be linked up to the airbox, however the carbs I have are not of this type and do not have this vent. There does not appear to be any obvious way (without a fair bit of drilling and taping of the carb body) to add a vent nipple. I understand the ram air effect really only makes a difference above 160 km/hr (100 mph), which I will not be doing very often (at least not on public roads anyway). I am going to check the fuel consumption, but suspect that the needle is probably too rich (it is richer than the FCR 41 spec). The bike runs well now, so the plan is to bring it back to my place (about 3 hours ride from where the bike is now) and play with it from there. As you say, all things being equal, the FCR39s should be jetted leaner than the FCR41s for the same bike. If I could just have access to a dyno and exhaust gas analyser for 1 hour, I am pretty sure I could make it run spot on. Maybe when I have a bit more money I might splash out with a dyno tune..... The carbs came with the bike. I thought they were FCR41s when I bought the bike (that’s what the owner thought as well and I don't think he was lying). As far as I know there are no external markings apart from the part number that distinguish an FCR39 from an FCR41. The carbs have the right bellmouth adaptors to connect up to the Guzzi airbox and the the rubber intake manifolds. Anyway I am pretty pleased with how it runs now and it has been a good learning experience, none of this tuning with a laptop like my MG 1200 Sport, but the old fashioned way with needles and jets and using the old seat of the pants dyno! When I bought the bike (for a good price admittedly), when starting from cold you really had to keep pumping the accelerator pumps constantly to keep it running and even then it was spitting and carrying on, and even when hot the bike would not idle and be spitting and surging when running below 5k. Now it runs really well with only a little surging when cold (which I would expect as the bike would be running lean).

Hi: Just thought I would post the setup specs for my Moto Guzzi Sport 1100 fitted with Keihin FCR39 carburettors, just in case someone else is trying to tune a bike with this setup (I could not find any specs for FCRs fitted to an MG 1100 Sport online). I have posted the specifications here for both FCR41s (advice from Keihin & Sudco) & FCR 39s (based on experience with my bike) as fitted to a Sport 1100. You take this advice at your own risk. When I bought the bike it was running quite poorly (too lean from off idle to 1/2 throttle [surging] and too rich at idle etc), I found that the jetting was way out. After jetting them to FCR41 specs it did run better but was still surging and not idling properly (too rich). I belatedly went back to basics and measured up the carburettor dimensions and found that were not actually FCR 41s as I had assumed (the only FCR kit for Sport 1100s), rather they are FCR 39s. Also unlike the kit, these FCR39s do not feature a ram air pressurised float bowl. After a fair bit of playing, the Keihin FCR 39s now run pretty well with the following setup. I think the bike is still running a little lean off idle (I think I will screw in the slow air jet ¼ turn and lean up the idle accordingly) and perhaps a little rich on the needle (might try a leaner needle, EMP or EMQ needles). I have deliberately kept the ½ to full throttle specifications quite rich to compensate for any ram air effect leaning the mixture (the FCR39s I have not allow for pressurising the float bowls unlike the proper FCR41 kit) and just to err on the side of caution (i.e. for engine longevity it is always better to err on the rich side). The bike is standard apart from a K&N air filter (with standard air box) and mistral crossover and cans (without DB killers). If I keep the bike long term I might go to FCR41s, as I would imagine that the FCR39s are restricting top end performance. Keihin FCR39 Specs (based on my bike): #155 main jet, #200 main air, #50 slow fuel jet (pilot jet), slow air screw 1 & ½ turns out, fuel screw (idle mixture) 1 & ¾ turns out, EMN needle (5th groove from the top). Keihin FCR41 Specs (from Keihin for a standard bike): #155 main jet, #200 main air, #55 slow fuel jet (pilot jet), slow air screw 2 turns out, fuel screw (idle mixture) 1 & ¼ turns out, ELS needle (4th groove from the top). Keihin FCR41 Specs (from Sudco for a standard bike): #155 main jet, #200 main air, #55 slow fuel jet (pilot jet), slow air screw 1 turn out, fuel screw (idle mixture) 1 turn out, ELS needle (4th groove from the top). Hope this helps someone. After rebuilding the gearbox (with a clutch replacement), giving the bike a full service and fixing a few odd issues and playing around with jetting the last 4 weeks, I am hoping now to start riding the bike and enjoying it! Thanks, Jason

Hi: Checked Trible, but they only seem to offer dampers for v11s. Given I have figured out to tighten up the steering play, I guess I'll ride the bike for a while and see how it goes. BTW GuzziMoto, have you got your Daytona going? How did the gearbox go? I ended up fitting a tonti gearbox set into my Sport 1100 gearbox case. The original gear set in the bike was actually in pretty good nick (mystery why it was so noisy through gears 1st / 2nd / 3rd), however the 3rd gear input gear was loosing its case hardening (all other gears were is great condition), so I had to swap over the gear set. Thanks, Jason

Hi everyone: The steering damper on my 1995 1100 Sport has leaked out all its oil and doesn't dampen the steering at all. A damper if you can get it costs around 250+USD. I was wondering if anyone has found a generic damper that can be made to fit the bike? Alternatively, what are the risks of running the bike without a damper? Do these bikes tankslap readily? Thanks, Jason

Hi everyone: Solved the issue. Had a close look and realised the "cap" was made of two parts, the top part of the cap was removable which then revealed the 8mm allen key nut. Thanks for the replies. Jason

This photo shows the cap over nut B: http://guzzitech.dk/wp-content/uploads/2012/01/GPS-2.jpg How do you remove this nut?

Hi everyone: Actually the manual (see attached image) does not show a cap, the nut is simply exposed with nothing covering it. I can easily access bolt A and nut C, I just can't get access to nut B as it is covered with a chrome cap (not shown in the maintenance manual or in the parts manual). I assume it is a cap and not the actual nut (without any hex or key hole in it, I don't know how they would have assembled it if it is a nut). The cap itself is completely smooth, there are no visible key holes etc. Without these holes, I don't know how to get it off. I am wondering if this is some type of accessory to cover the nut itself. I know the bike was first owned by a manager at a Moto Guzzi dealer, so it could be an accessory. The cap shows a few indentations where it looks like someone has tried to remove it before. I assume that the play cannot be adjusted with nut C without loosening nut B? Does nut B need to be removed to remove the whole top triple clamp? Thanks, Jason