motoguzznix

There are two angles to be considered: The rocker arm to the valve. Can be adjusted by shimming the rocker spindle bracket. At 1/2 valve opening the angle must be 90°. Attention: this changes when the valves seats get deeper or when a cam with a different valve lift is used! This must be adjusted first. The rocker adjustment screw to the pushrod. Here very similar: at 1/2 valve ópening the valve adjustment screw must be in line with the pushrod. This is not academic. Setting this right makes the valve train work as it should. At first sight the difference won't be big. But after 50 or 100 thousend km the valve train will be in a very different state of wear.

By design the stock pistons seem to me the stouter items. Maybe you can use the lighter pins in the pistons if the length is the same. Concerning the combustion chamber design the stock pistons combined with milled heads is the better solution. You will get squish and a more compact chamber with less surface area. Both keep the engine away from pinging. CR will go slightly above 10:1 (mine started at 9.15 from the factory) which makes no need for a twin spark. When the pushrod length is not correkt (being too long or short) the valve lift curve géts asymmetric. You can observe this when you look at the connection where the pushrod meets the valve lash adjustment screw at the rocker: At closed valve there is an angle to the one side, at full open valve the angle is to the other side. This angle should be the same left/right. If this is the case, rocker adjustment screw and pushrod are exactly in line when the valve is at half lift. If the pushrod length is incorrect or the valve seats get deeper after reworking, this symmetry is disturbed. This means the angle pushrod/rocker gets tighter to one side thus increasing the valve train wear. Additionnally the maximum possible valve lift of the cam will not be reached. Keeping in mind this I think it becomes clear what direction to go. Just my

But there are advantages too: If you use a reground cam, the base circle has a tighter radius. When you mill off the head and shorten the cylinder barrels to get a working squish arera, the reground cam helps you to cope with the stock pushrod length. Otherwise the pushrods shoud be shortened to keep the valve train geometry when the cylinder/head length gets shorter.

Tom Those new pistons are indeed a completely different design compared to the older ones. Apart from the fact the newer ones are sliper pistons, the dome height seems to be lower than stock. Maybe these pistons reduce CR. They look like the high compression pistons for the Cali 1100. That explains why they can be used without any other mods on the engine. For your understanding: There is no squish without machining the heads. Believe it or not, the engine would benefit from squish an the ping issue would decrease. And you have not to compensate for the reduced thickness with the gaskets - you would loose the raised compression and the bigger squish height would make the squish inefficient. One question: Could you measure the weight of these pistons and the stock items? And post the figures here? The stock ones are very heavy and the piston pin too. Maybe in that area gains are to be made?

Tom be careful concerning the FBF pistons. These pistons are of a very unfavorable design for the V11 engine. First point is you have to mill off the cylinder barrels to get the pistons flush on top. The photo shoot above suggests the same compression height for the stock and the FBF piston, so the same amount has to be removed from the barrels for both oof them. Second point you have to mill off 1 mm from the heads to get a working squish area. Remember the chamfer. Both measures increse the CR of the engine. Both measures are necessary to get a correct working combustion chamber design. Third point the FBF piston in addition raises the CR further. But the higher dome makes the combustion chamber worse and more prone to ping. So you have 3 measures that increase CR and thus pinging, Fourth point the higher dome worsens things further. If all is done correctly, there are two measures that detract from the pinging issue: Valve stem play like new prevents the oil contamination of the combustion chamber. The now existing squish makes the mixture in the comb chamber less prone to ping. The extra CR of the FBF pistons is not an asset for me. Maybe the CR gets so high that even twin spark is unable to cope with this engine. And without the ability to change the ignition map there is no way to make this setup work. Why not proceed with the stock pistons? They don't look bad, the missing coating is no real problem. If the play is within the wear target, there is no reason to throw them away. Or mill off some mm from the FBF piston dome if possible.

Slavomir Sandblasting is no good idea on piston and head. Te sand causes deep grooves in the light alloy which is not desirable. For removing the carbone deposits I always use stainless steel wool. Should be in every kitchen. Cleans good and the surface looks almost polished. Polishing is a good idea for the combustion chamber surface as the heat will be reflected and enters piston and head in a smaller amount thus increasing the VE of the engine. The deposits are not caused by the blown head gasket but by the worn valve stems and guides. Check this before reassembling!

Henrik It is not the air pressure measured by the Siemens ECU but the MAP (manifold absolute pressure). This is a completely different approach to the injection nozzle opening time calculation as you get a much better information about the load condition of the engine. The Weber ECUs are not able to handle this information as Hubert mentioned. Even very simple car injection systems work with a MAP sensor, but it was not common in the motorcycles yet.

STOP!! It was a joke, wasn't it? A plain bearing can not be adjusted to zero play as the brake away torque will increase dramatically. A steering head bearing with brake away torque is a disaster! A rotating plain bearing supplied with oil pressure is almost friction-less, but these conditions do not occur in a steering head.

David The start/kilswitch housíng is likely to deform when the screws are tightened too much. I reworked the starter button hole with a small cutter knife to get it square again. Since then the button nerver sticked again.

Some years ago I did some A/F measurements of my KR V11: A/F graph stock KR The stock engine runs very lean at approx. 2900 rpm which explains the "miss" sufficiently. Richening the mixture via a power commander or some other device at that engine speed will make this issue disappear. Mine also pinged at that rpm accelerating at full throttle. A very careful tune up of the injection system can also make the symptoms much better.

I agree the attachments to the engine was the most important change. Mine weaves above 150 km/h. It was better with the BT010 tires, I think they are soft and show good dampng effect. At my opinion, the insensitive front fork is the main reason for this. My forks do not respond to slight bumps, so the bumps are transmitted into the frame. Time is coming soon to evaluate my theory, as I am converting my suspension to Öhlins. In two or three weeks I hope to be back on the road.

The V11 was designed by Guzzi prior to the Aprilia takeover. The short frame was not stable above 150 km/h where massive speed wobble occured. Also on mine, was better with the BT010 tires and got worse with the Z6. To overcome this, Aprilia launched the lenthened frame, changed the subframe front and introduced the attachments from the rear subframe to the engine. The vehicle is now absolutely stable up to topspeed, but handles slower. Returning to the photo above: As you can see, the steering head is welded onto the frame in a lower position, which gives a further variation in the wheelbase department. Complicated indeed...

Very interesting, thanks for clarification. So Guzzi did it vice versa than I would do it and the conversions by Paul and Mille108 did it. They lengthened the wheelbase and increased the caster by two or tree measures to make the vehicle more stable at the expense of the manoevrability. I like my lightfooted KR frame.

Ratch I was always of the opinion that the later frame has the steeper rake angle and the frame was lenghthened to keep the alternator cover clearence. So one measure makes up for the other wheelbasewise. 1 inch longer frame, 16 mm less due to the steeper angle is a difference of approx. 9 mm. To bring one more fact on the counter: The newer bikes have the forks lenghthened which contributes to more wheelbase. The difference in frame length is clearly visible as the distance of the breather hose connection to the steering head is bigger on the new frames.

Slavo disconnect the black/red wire from the regulator. Should work then.

Sorry - should work now

Hello Christian thanks for your reply During the last two years I had to build a house for my family and my bikes, so the effort for the Guzzi stuff was very limited. But now I'm going to get my V11 back on the road. Concernig the heads I started by slightly reworking the port in the area indicated by the arrow. As you would expect the effort was almost zero. The next step will be to enlarge the port around the valve guide. I have one spare head to play with and I intend to enlarge the port in little steps and check the effect on flow. As soon I get results I will share the information here. Some information about the rebuild of my V11 you can find here - for german speakers: http://www.world-of-guzzi.de/forum/index.php?topic=27638.0

It sounds like the starter relay does not work. This is the one with five contact pins. If this does not work properly, the lights are inoperative too.

brake cleaner Every change in idle speed indicates a leak in the intake line. According to my experience the idle speed decreases when a spray of gas is applied.

arek if oil is passing via the valve guides into the combustion chamber, there should be oil in the port too. If the ports in the wet cylinder are both dry, the oil must intrude somewhere else. Either rings or a crack in the cylinder/head might be the reason for this. When dismounting the valves chances are high for the guides to be ruined. I would take a look at this. Sometimes the oil passes on the outside of the valve guides if they are loose.

Hey thanks Raz, I didn't remember I ever posted a cam graph on this forum. From the measured lift of 10.5 mm you have to subtract the valve play. Most important for the timing figures is the valve gap used for the measurement. Guzzi quotes this at 1.5 mm with a duration of 256°. My measurements show 254/253° which is very close. Better than measuring these figures is adjusting by measuríng the max valve oift of intake and exhaust.

Here is a german Cantauro Conversio. All done by the owner Dirk including the Tank manufacturing. Dirks Website The company V2 Moto in Berlin/Germany has built some V11 with Centauro engine.

If you disassemble the bike, check if the clutch gear has a tight fix at the gearbox input shaft. If loose, gear oil can intrude into the clutch causing her to slip. If there is only the engine or gearbox seal seeping, the clutch rarely begins to slip.

you are right concerning old threads Since the early days of the "open the cans" thread I modified another V11s exhaust cans in the same way. This bike responded even better than my own V11 on the modification. Additionnally I took some photo shoots during the work. This convinced me to post the results again. The gains are not so small: 3 RWHP on my bike and 4.5 HP for the second bike. And you can feel the difference while driving, it's not just dyno figures. 90 % of the aftermarkeet cans that are fitted to the V11s around do not show any bigger gains without A/F ratio changes. But my modified cans did also benefit from mapping changes: Torque climbed from 8.8 to 9.5 mkg, max power was about the same but the gains between 5k to 8k were up to 6HP. When I fitted open Leovinci cans, neither max power nor torque was any better, only the torque minimum at 4000 was slightly up from 7 mkg to 7.5. But you still have the heavy stock cans. It depends on you if you like the looks or not. The modifications are unvisible from outside as all the welding seams are underneath the oval light alloy covers. There is everything written on the cans an officer likes to see and they will never arouse suspicion as they are only marginally louder than stock - slightly deeper tone and even at high rpms just a bit louder. That's because the complete volume of the cans is still used for noise reduction while flow resitance is reduced a lot. And weight helps reducing noise. There is only one disadvantage: you can't bye it cheap on ebay. You have to du some work yourself. Not everyone is able to do this and not everybody would like it. But for those who can and like to spend the 2 - 3 hours of time there are good gains for your .