Guzzi07 Posted April 1, 2012 Share Posted April 1, 2012 Hi everyone: I am having problems with gear noise (whining noise that increases with speed, it is quite loud) in the first 3 gears (4th & 5th are fine), which increases under load. It appears to be a little unusual as the bike has only 38k on it (the rest of the bike is in very good condition). I am new to the bike and don't know the history of this problem (I know staight cut gearboxes are noisy, but I am sure they should not be this noisy). It appears that new parts are no longer available for these straight cut gearboxes. I understand from other information sources that it is possible to buy up a 5 speed big block gearbox (from any other model) and transfer the internals in the Sport Carb box casing. Has anyone actually done this? Is it a straight swap? Thanks, Link to comment Share on other sites More sharing options...
gstallons Posted April 1, 2012 Share Posted April 1, 2012 Drain the fluid n tell us what you find................. Link to comment Share on other sites More sharing options...
Slavomir Musilek (R.I.P.) Posted April 1, 2012 Share Posted April 1, 2012 Hi, You have the carbs, right? Now you have to find if you have straight or helical gears. Helical gears are on later models of carb Sport, and on all Sport IE and so on. The straight teeth are prone to be made out of finest italian parmesane and noisy gears indicates there is something bad about to happen FYI - these are my gears taken out from Carb Sport with 70000km on the clock (I think that number should be multiplied by two). All gears showing signs of pitting. Getting new gears costs a fortune and is nearly impossible. So what you have to do is to find healthy Gbox from Sport IE, Centauro, Daytona... It will fit with no problems and the differences in gear ratios are not tragic. Used Gboxes can be found at price of 400€ or so. Send message to Pete from Reboot Spares and to Gutsibits. I had many replies also from DE forum www.V11sport.de Good luck! Link to comment Share on other sites More sharing options...
Guzzi07 Posted April 2, 2012 Author Share Posted April 2, 2012 I will be carrying out a full service in the next couple of weeks when I have the parts. Will be looking closely at the oil and drain plug, but am pretty sure there is a problem. I am guessing the bike was ridden a lot around town which would account for why the first three gears are the problem whilst 4th & 5th seem fine. I checked through the oil filler hole, and the bike has a straight cut gearbox. Reboot looks like the best option. Thanks, Link to comment Share on other sites More sharing options...
GuzziMoto Posted April 2, 2012 Share Posted April 2, 2012 I currently have a Daytona that I am putting back together. I bought a Bassa trans and used the gearset from that in my Daytona box. I also used better main bearings with steel instead of plastic cages. I am just now getting it together, I am also re-wiring it and finishing up some other mods. I hope to have it back on the road in a week or two. Time will tell how well it works with the Bassa gearset. I am hoping for better shifting and smoother, quieter running. The slightly shorter gearing should give it more acceleration as well. If you search you should find a fair bit of info on the Guzzi 5 speed box, both how to set it up as well as short comings of the various versions. Link to comment Share on other sites More sharing options...
Guzzi07 Posted April 3, 2012 Author Share Posted April 3, 2012 GuzziMoto: I would be very interested to know how your modified gearbox goes. I saw Pete Roper's comments on this option, though before I start thinking about buying another gearbox I really wanted to hear from someone who has done it. This really would be my ideal solution for a number of reasons: 1. Easier to find the parts for the job. 2. Quieter operation of the gearbox. 3. Improved cush drive system (coil spring versus stacked washers). 4. With the 5 dog gears, less freeplay through the drivetrain. 5. Lower gearing making for better acceleration and less stress on the clutch. Jason Link to comment Share on other sites More sharing options...
GuzziMoto Posted April 3, 2012 Share Posted April 3, 2012 I will let you know. It will be at least a week or two before it is on the road. The wiring aspect of this is a bit deep. I have wired up bikes before but this is the first fuel injected bike I have done and because of the rarity and lack of parts availability I am cutting up a harness from a different Guzzi to use as the donor for the modification. It is very close but not the same. I am pretty sure it will work..... Link to comment Share on other sites More sharing options...
Guzzi07 Posted April 22, 2012 Author Share Posted April 22, 2012 Hi everyone: I checked the gearbox oil and sure enough it looked like a metal christmas tree. I have just pulled the gearbox and wanted to ask a few questions. After splitting the gearbox from the engine I noticed a bit of oil in the housing. The clutch worked well with no problems the few times I have riden the bike. In particular the large gear that splines with the clutch and the puck in the clutch (which holds the clutch pushrod), were both visibly oily with gear oil (had that unique smell). The surface of the flywheel (clutch pressure plate side) was also oily to touch. Given this oil appears to be gear oil, I can only assume the gearbox input seal is leaking (which will be fixed with the gearbox overhaul). However there was also some oil behind the flywheel on the engine side, there is no evidence of running oil, the surface is just oily to touch. Should I be looking at the crankshaft oil seal? Or is it normal for the surface to be a little oily? Thanks, Jason Link to comment Share on other sites More sharing options...
dangerous Posted April 22, 2012 Share Posted April 22, 2012 looks like you have the right tools for the job... a big fark off shifter and 2 hammers ;-) The guy that brought my 97 sport (injected with straight cut box) at 90.000 odd k replaced the box with one from a SP or like. Link to comment Share on other sites More sharing options...
dangerous Posted April 22, 2012 Share Posted April 22, 2012 FYI - these are my gears taken out from Carb Sport with 70000km on the clock (I think that number should be multiplied by two). All gears showing signs of pitting. Is that a straight cut or helie box you show there? Link to comment Share on other sites More sharing options...
Slavomir Musilek (R.I.P.) Posted April 22, 2012 Share Posted April 22, 2012 FYI - these are my gears taken out from Carb Sport with 70000km on the clock (I think that number should be multiplied by two). All gears showing signs of pitting. Is that a straight cut or helie box you show there? Hi! The gears are from the straight cut gbox. The one shown mounted is gbox from Centauro. Slavek Link to comment Share on other sites More sharing options...
dangerous Posted April 23, 2012 Share Posted April 23, 2012 The gears are from the straight cut gbox. The one shown mounted is gbox from Centauro. Slavek interesting so whos got a helical photo to post up? Link to comment Share on other sites More sharing options...
Guzzi07 Posted April 23, 2012 Author Share Posted April 23, 2012 Yeah after I uploaded the photo, I had a look and thought the 3 tools in shot looked a bit rough. The 1/4 inch drive tools are out of shot The nuts locking the swing arm in place and the bolt attaching the breather hose to the sump, were so tight I had to use that huge shifter to undo them.... Link to comment Share on other sites More sharing options...
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