Chokes Dual-firing Ignition Electrical System
Gear box Clutch and Flywheel Oilpan U-joint
Airbox Headers Timing chain Camshaft
Cables Handling Front fork
Guzzi Tech Papes

last revised 22. november 2001


The chokes are usually operated from the handlebars and are transmitted then by a distributors under the tank to the individual carburetors. The friction of this system is naturally quite high and there are additional parts, which can break or stick. This ends up creating a too fat mixture and bad engine running. You usually observe it just in idling.

I use the flipchokes, which are available in every well equipped Guzzi Shop. These things are screwed directly into the carburetors and must be lifted to operate. Here they are not easy to reach, but usually you can snap one or both in as soon as the engine is running.  


Originally I got it installed to be able to burn low quality gas, that was before my vacation in the Baltic State.  Unfortunately the ignition broke down beforethe trip and I had to start this journey with the original set up. However, now it's working, but I still can't use low octane gas, it still pings.

Also for the mounting of the coils I spend some times in thought. The stiff mounting proposal, which was recommended from the supplier company Silent Hektik, was actually the cause of the first coil death. Now I mounted them isolated by some foam to the frame between the cylinders. 

The dual-firing has given the motor a quieter idling, I can not say indeed, that there is more power. It runs generally more quietly. Whether the fuel consumption has decreased, I can only comment carefully, because I have never ridden the engine in exactly this constellation without it. However, compared with some other Guzzis with similar engines, I would estimate an advantage of 0.4 l/100km. That's not much. But with regard to the recent engine rebuild it was a good decision because the big single bore needs strong ignition to work decently. Idoubr that it would help an average rider I would doubt, and it is not really a bargain anyway 


I am someone who ties to prevent defects rather than searching afterwards for the defect at the roadside. Not just on old Guzzis, I always stat, to treat all plugs with acid grease, to avoid electrical breakdown caused by disconnection due to corrosion in the plugs. You have to spend half a day of work, but than there is silence in the box, as we Germans say.

The SP1000 had at the beginning a serious ground problem. That is also symptomatic of every old Guzzi. In effect I have everything, which was not directly connected to the frame, wired to one single bolt at the frame, which I connected with one big wire to the battery. 

Meanwhile I have checked through my whole wiring system. There are a lot of cables, which are built in, because other models need them. I also reduced my check lights, having in mind "when there is nothing, there is nothing to break". This I would only recommend to somebody who has a solid knowledge of electricity. By this method, I reduced my wiring system for about 4 meters. During this operation, I also eliminated all unnecessary plugs, especially the big ones under the tank, which sometimes got disconnected on their own. I soldered all cables together and isolated them with shrinking tube.

Also the head lamp was too dark. I checked through the wiring plan and discovered that all current was passing through the light switch and always 1 Volt less than at the battery reached the bulb. Now I changed the system to a relay operated circuit, where battery voltage is switched by two relays for low and high beam. The effect is a brighter light.

The same is true for the starter circuit, which is led over the kill switch and ignition key. I used the same system and got more power at the coils. 


The gearboxes of Guzziís are - at least in the older models - not really start-of-the-art. Due to big tolerances, shims are used to eliminate them. Mostly that is not properly done, so that changing gears and finding neutral is more a question of luck and patience. But even at my 1000S made in 1989 it was after 100.000Km not possible anymore to find neutral immediately. I have given it for shimming to Dynotec, a local Guzzi shop, and have not regretted the 350DM. Now I can change gears with the tip of the toe.

The SP1000 had also gear box problems, whereby the most annoying thing was also here, the difficulty to find neutral. Finally, when I had to take the gear box apart because the return spring was broken (something I would always change, if the transmission is open), I took the Guzziology book in one hand and the spare set of shims in the other and took a chance. This book is written by an American mechanic from Seattle, who has wrenched his whole life on Guzzi and is member of the Moto International shop.

Without going into detail, here is only a short description. Put the rear cover in a vice, so that all shafts stand vertically. The goal is to bring the shift drum into a position where the shift forks are equally engaged into the shaft rings. For that you use the shims under the shift drum. If you think youíve got it, mount the box with the drum together with the rear cover without gasket. Try to turn the shift drum through the holes in the housing. If that works, rebuild the whole thing with all shafts and try to shift by hand.

But this is only a very rough description, I would recommend for enthusiastic wrenchers to buy the Guzziology, where more details are given. 


Many criticize the bad handling and the uncomfortable seating position of the 1000S and the LM models.  I totally agree, the first ride with original handlebars was also the last. I mounted a higher set and now it handles perfect.

Because the original seat was worn out, I invested in a Corbin seat from a LM II, which after some adjustments was also possible to mount on my 1000S.  The advantage is better seating position, where the rider is more integrated into the machine. But it is not a good recommendation for smaller riders, as the saddle is wider and you will have problems reaching ground. 


The universal joint has the reputation to last not very long. I personally have had no real bad experiences with my 1000S. However on the SP1000 I had to change it once at 40000Km. After all the stories I had heard, I searched for a solution for long time to prevent  any roadside work. The fundamental problem of the U-joint is, that it warms up and the seal dries out. For that reason I mount a carrier bearing without a seal which allows the oil from the rear housing to pass by through it, lubricating the U-joint. Add to the oil in the rear housing an extra dip of 30ml. That worked on my 1000S for 150000km. It's not difficult to do.

But it doesn't work on models with the thin rear swing arm, because there is no space for the oil to flow. But you can get a similar effect, with a 30ml fill-up of the U-joint housing. Just use a syringe for that. 


What kind of improvement is there for the headers, you wonder? No direct improvement of the headers, but by them. The original big twin engine with the big valves like in the LM IV has problems showing decent power under 3000rpm. I experienced a very big improvement with the help of headers with a larger diameter. I have headers with 48mm, but there are also 42mm available. My bike showed after mounting this pair, without any other change, a behavior where it was no problem driving 1500rpm or less through villages in fifth gear and accelerate afterwards (forget the oil pressure for a moment). This is the power you expect from a Guzzi.

Just recently with the lastest dyno reading I got convinced by a set of 42mm headers with crossover. The were in higher range much better than my old "big ones", though I never regret to use them before (see also Diagram


A pain in the ass is the airbox  of the big twins. The change of the filter element is a task on its own.  Additionally this thing also becomes fully saturated riding in the rain and you can drive not faster as 120km/h because there is not more air passing through it. Annoying!

If you are also victim of this behavior there are two available solutions. Either you ride only under good weather conditions and use frequently the help of your garage, or you cut a hole in the upper rear part of the airbox. Leave the filter element in (you can remove the snorkel), to keep the big shit coming from the front out of your carbs. The opening (5x5 cm) I covered with some wire screen. After giving your bike a bigger main jet and readjust the idle, it should drive better than before and you even got some more horsepower for free. Isn't that great? 


As I have learned in the first year, that the LM IV engine has a serious lack of power around 4000rpm. To overtake somebody, driving in this range, you nearly have the feeling that you have to shift down.

For it this reason I purchased form the German company Dynotec a new camshaft which eliminates this lack of torque (see also DIAGRAMS). With their 7006 camshaft  you have sufficient power everywhere available. This one I have used with my original displacement of 942ccm. with the big bore kit, I use now of 1105ccm, it was necessary to change to the 7906, which has a bigger inlet opening of 7,9mm.  The owner Jens Hofmann is quite arrogant and I had also some problem with the quality and the work on the delivered parts and will not buy anything in this shop again. But there are different others as HMB Guzzi or Stein-Dinse.


The oil change on a Guzzi is not really fun (doing it properly). You have to remove the oil pan to change the filter. At one point in time the always heard reason "it's good, because you can check, if there is something in your oilpan" didn't convinced me anymore, because there was never anything in it. So I looked for another solution.

The solution with the ring with the filter in front did not please me since here the oil is cooled in rain so much. My oil anyhow never warmed up so much. I measured with a gaged thermometer never more than 110 C, that's under hot conditions with 35 C outside temperature and at 150 km/h steady speed. Indeed there was a similar principle with the filter in the rear under the gearbox. Because I don't have a collector anymore, there was enough space. It works fine and changing oil and filter is now a 15 minute job.

Now with my new engine, which produces more power, I had the choice of an oil cooler or a bigger oil pan with the filter in front. I chose the bigger oil pan, to have not an extra part added to my engine. Because the engine becomes hotter anyway, the filter does not do any harm. 


I personally think the original timing chain principle is compared with the belt or gearing system the most reliable and cheapest system on the market. The problem is only the tensioner.

The ancient tensioner from the first models consisted only of a movable sliding rail. Who in the world takes off the front cover frequently, to  check and adjust the tensioner. When I changed the tensioner and the chain at the SP at 50000Km there was a 10mm gap even under the best condition.

The tensioner of the 1000S was more sophisticated. A little tiny rail was pressed with a equivalent weak spring against the chain. It was no problem to move it with the small finger. It found itís way directly into the garbage bin.

Remove this scrap and end unstable idling and loud engine noise. There is a better alternative on the market, called here in Germany the Stucci tensioner. It consists of a plastic rail, stretched by a spring so much, that it is even hard to build it in - costs about 30DM. To build it in, take off the nut, pull the tensioner off the axle so that the spring just stays in place and then push it between the housing and the chain. The last one lasted for 120000Km and I only exchanged it because the engine was open anyway. 


The cheapest way of getting the feeling of having a more agile engine is to lighten the clutch and the starter ring. Here you can easily get rid of 2,5kg. This is only the reduction possible on the sport clutch, the touring models have half a kilogram more to accelerate. My initial skepticism that the idle becomes unstable was not confirmed.

You can certainly also buy one of these expensive Ergal or one-disc systems, but from what I have heard, none of these are as reliable as the original one. The other advantage is that you can always use the original, reasonably cheap clutch discs. I was still able to use the whole clutch after my 205.000Km renovation of the engine.

I have also reduced the moving masses in the engine by installing a pair of Carillo push rods. I had the chance to get a pair directly from the States for a better price. I cannot say that there is much difference to feel. 


The 40mm front fork of the 1000S is not just the big hit. In the original condition it is much too soft and damps too hard. Just in comparison with the SP1000 it strikes me that there is never any doubt about the road conditions, where the SP simply moves over it (however it has other weaknesses). Many people have also the problem that their front fork bottoms out and leaves these ugly bumps in the front fender. On one 1000S, I even discovered missing front oil as part of the problem.

When I took my fork apart, I discovered a leaking damping element. The substitute would have cost more than 400DM, but after some telephone calls I found out that there are all spare parts available. So I paid 25DM per sealing unit and replaced them both immediately. One of the plastic pressure plates at the bottom was the reason, it broke and stopped moving so that the inner pressure of the damping unit became weird. I also filled the unit with thinner oil. The springs I changed in favor of a pair with progressive behavior.

The success was however moderate. The fork responded somewhat better, doesn't bottom out anymore.  But it was still too hard. So I shortened the springs to a minimum length, which is just enough to stretch the damping unit to maximum. Loaded with one person, the bike now uses 25% of the whole possible fork travel.

I have supplied my machine also with rubber covers. Fork seals die nearly always the dirt death, caused by dust and the dead flies sticking to the fork and rubbing through the seals. My seals have now lasted 220000Km. Then I had to change the whole fork, because there were scratches on all parts. 


Breaking cables are nothing special on a Guzzi, also I had to change my cables frequently every 30.000Km. But now with trying different routings, I have found a position, where they last 60.000Km. Just keep trying. 


As you perhaps learned from all the stories, I am basically a quite lazy person, who tries to avoid unnecessary work where possible. Considering this the point ignition was and is the most annoying point on the original Guzzi. I have driven it for a year and I have never adjusted the points to my satisfaction. After 2000Km this scrap has lost it's adjusted position again. So some other solution has to be found.

The best attempt was Piranha, sometimes also known as Newtronic. Very much cheaper than all the others. As a rough estimate you can get it for around 300DM. The technology is very simple and the components interchangeable. It consists of  a light barrier with small breaker and a control unit. Quite simply usable. I had to widen the holes in the mounting plates to get the best values for both cylinders. I have adjusted them first statically and later on checked it with the stroboscope. If one part brakes it is possible to get all parts as single spare parts. The installation of the pointless ignition not only saves work, but also gas. The consumption decreased for about half a liter per 100Km.