emry

Here is some casual reading. http://www.bosch.com.au/content/language1/html/4557.htm or http://apps.bosch.com.au/motorsport/downloads/regulators.pdf and http://apps.bosch.com.au/motorsport/downlo...chtip0505_1.pdf and http://www.auto-ware.com/combust_bytes/eng_sci.htm or http://en.wikipedia.org/wiki/MAP_sensor Maybe some is related to this ever growing thread. Cheers.

Constant throttle, constant rpm, going up hill = High load, the engine is overcoming the mechanical losses in addition to gravity, etc. Same throttle, constant rpm, going down same hill = Low load, the engine is being driven by the rear wheel which will help over come the mechinical losses, etc. Yes going up the hill we would end up opening the throttle to maintain a constant rpm and going downhill we would close the throttle to maintain a constant rpm. We often forget that our engine to run at constant RPM the crankshaft really us undergoing vast changes in accel and decel. During just after TDC compression our expanding fuel mix is exerting a great amount of pressure down on our piston, our crankshaft is in a state of acceleration. After approx 3/4 of the power stroke our crankshaft now is transitioning to decel. It continues to undergo a reduction of rpm with the greatest amount of decel during the next compression stroke. Yes our second piston will affect this, but lets keep it simple. Up hill our mechincal efficiency is decreased, downhill our mechanical efficiency is increased. The volumetric efficiency of an engine is a function of its mechanical efficiency. Volumetic efficiency is a measurement of how well an engine fills a cylinder to its capacity. Yes it can. Our bike are an example of this. But it will never be better that its orginal estimate of the predicted airflow through an engine. Do our engines run differently with tight or lose valves, why cant a alpha-n system compensate for that?? It has no way to measure airflow. It merely knows what should be going through. Which may or may not be the case. Valve setting affect our valve timing and airflow right?? A MAP sensor would relay that info to be used for fueling calculations.

Airflow unfortunatly does not like to operate in freeze frames. While our engine has a fixed cylinder volume, the air that makes it into it is a function of many different factors. Load is one that will affect the flow of air through the engine. At any given moment our airflow may be different than a previous moment, even if our TP angle and RPM are constant. Since manifold vacuum is directly proprtional to load this make for a effecient method of computing pulse width. Clearly a alpha-n system is capable of working very well, a well set up speed-density system is just more accurate, just as a mass air system is still more accurate. More accuracy means better economy, less emissions, more power, hopefully less pinging on accel and less popping on decel.

Speed Density systems are able to calculate the volumetric efficiency of an engine courtesy of the Ideal gas law. Alpha-n systems are simple preprogrammed fueling maps. Intake airflow does vary under different operating conditions, such as engine load. SD systems can provide much better fuel mapping for low throttle settings and slight changes in TP. Many SD systems revert to a Alpha-n system during acceleration or above about 30% throttle opening where airflow through the engine to changing too quickly for a MAP sensor to be accurate.

I had a few "bad" buld that turned out to be poor connections at the base of the bulb. A little fiddle of the contacts and some cleaner was a quick easy fix.

Much like Ratch I did examine the the front seal, and all seemed well, but then a few days later after reassembly a slight oil leak was present. Ordered, pulled and replaced the front crankseal and all was well. Save your self the few extra days of fustration and have a seal on hand. Me thinks the abiltity to accutately relocate the front cover in the precise location as its disaasemly is a hit-an-miss affiar. Pete or RacerX? any luck not replacing the front seals?

Do a search for "timing gasket" it should turn up something. I have blown this gasket on the other side of the chest 3 times before doing away with the gasket and using some hylomar instead, has not leaked since. Be Sure and get a front crankseal to install while you are at it, they are not very good about being reused, luckily they are cheap though.

Just curious. My first poll, wonder what I screwed up.

In addition, to do a drop test on the posistive side of our primary soleniod starter circuit, you would put a meter lead on the positive battery terminal, and the other on the "hot" small lead that is going into the soleniod. Initially the meter will read 12v. o so. When we press the stater button the reading should drop to 0.0v But in the real world as long as it does not drop more the 1.0v our circuit should be fine. Everytime our current passes through a switch we will have a small drop and these will add up, as long as our switches drop less than 0.5v everything should work alright. If you have a problem then you could start to split the circuit in half to pinpoint the afflicted connector or switch.

Sorry I have been away but I sounds like you may have it resolved. Just for clearification the primary side of a relayed circuit is the side that controls the relay (or soleniod) and the secondary is the side that normally will have the high amp's. So in our starter circuit the starter switch, sidestand etc. is on the primary side. The secondary side really just consists of the high amp lead to the soleniod, soleniod to starter, and from the engine to the batt's negative terminal. The purpose of a voltage drop test is to locate a point of unwanted resistance in a live circuit. As electrical current (amps) is pushed (by voltage) through a load (resistance) it will lose voltage. Thus a "voltage drop" To easily check a portion of a circuit, our ground lead for example. Set your multimeter to measure volts DC and attach a lead to the batteries negative terminal and the other to one of the bolts that hold our starter to the engine. The meter should read 0.0v We are simply measuring the difference between the two points. Continue to measure and operate the starter, the meter should stay near 0.0v. Anything over 0.5v would indicate a bad connection. By doing this we just checked the connection of the starter to the engine, the ground wire from the engine to the battery, and the ground wire to battery. Doing a voltage drop is a much more accurate test of a circuits ability to pass current than using the Ohm function to check a circuit staticly. Just as a note you can have a problem on the primary side of the starter soleniod and the soleniod will not operate normally, sometimes it will simulate a low battery, "click click click" or a very low battery "urgnnnn..." When you check the battery the voltage will be fine. I have seen many people put two or more batteries in a bike berfore fustration sets in and they take it to a shop. Cheers

Do you know how to do a voltage drop test? The odd groan from the solenoid is due to low voltage on the primary side, either you have a poor connection on the positive or the ground side of the solenoid. That helped didn't it. A quick voltage drop test can quickly locate the missing volts. I do not have my schematic handy. I will try and find it and see if I can come up with more precise test for you. It my be hit or miss as my Scura is 200 miles away. Wiring Diagrams courtsy of Mr. Carl Allison who is active here. the 1999v11 should be close enough to head you in the right direction. http://www.thisoldtractor.com/guzzi007/sportissimo.html

To each their own I guess. While I do have to side with Ratch on the above creation I still really like this one. While this does not really apply to this topic I was just curious, is this the infamous Mr. Roper?Pete???

I think that the intake length should be close to correct, if I recall from another thread our current intakes are to short. The DHLA's actually are two carbs but they use a common float chamber, each side is individually tunable. I just had to tune up an old Lotus Turbo that used them. The HD I saw belonged to an old grey beard, he was certain that his HD made more power than my Kaw GPz900. He missed out on the whole tuning thing because his carb was about two inches from the valve (common on HD's) and his exhaust was about three feet long and two inch in diameter. Beyond the flames it also holds the record for the loudest motorcycle I have ever been near. It was running in a Dynojet chamber that it left burn mark on the wall of. We were outside the "sound proof" chamber and it still hurt my ears!!! By comparison you could talk normally when a standard bike was running.

Looks like a Dell'orto DHLA. Harley guys love them, more fuel, more noise, more power!!!! I saw a 100inch HD with straight pipes run on a dyno years ago. It shot 2 foot flames out the exhaust when it was wide open and made a whoping 48HP!!!! We about wet our pants we were laughing so hard.

Loudly, I imagine.

That is my impression. I too would like a little clearification, perhaps Jaap will offer a follow-up since there has been so much confusion and concern.

I emailed Jaap after I got the email. He responded that it was not directed towards me but that it was a general warning to all. I would seem somewhere a few members "pushed some buttons." It is unfortunate that a wonderful site such as this is in jeopardy of being turned off because of the actions of a few. Hopefully the intended targets of the mass email will take heed and move their inappropriate comments to the appropriate place. Else we all lose. I've been here since 02 and would like to stay.

If Pete did not spend so much time with rubber chickens he could have programmed this. Just a graphical example of pressure increase during combustion. Java Applet of Otto Cycle engine. I can not find any reference to the actual pressure being calculated perhaps someone else can. ???Bar??? For those of you that are kinetic learners loosen one plug up til it is just barely held in, start engine and rev. Small tip - don't stand on the side of the loose plug. Really though, don't try this... trust me...

Most automakers now employ lean burn fuel curves for steady state crusing and idling. The curves then switch to a richer setting as required by calculated load. Advances in combustion chamber design and catalytic converters has keep the otherwise poor emissions in check. Honda has been doing heavy development of extreme lean burn technology for use in their hybrid drivetrains and other economy cars. Ratios of around 22:1 are fairly common now with as high as 50:1 being used for future direct injection engines.

Ok, scratch that search, I just tried and couldn't find it. I know I was here somewhere. Ratch, you got a clue?

I think the tachs do it all over. At least mine did and I live in the southern US. Do a search for drilling tach. That fixed my problem.

I highly recommend replacing the the crankseal. It is a delicate little fellow and the chances are pretty good that it will leak afterwords. As for the gasket I blew out three withen about 7k miles. Finally used some Hylomar instead of the gasket and it has not leaked in the 4k since. My rotor slides easily off, but yours???

Air gap affects only affects the shock during about its last 1/4 of travel where it produces a rising rate curve that adds to the effective spring rate. This is normally adjusted when there is a bottoming problem but the rider is happy with the current spring rate. i.e. the front travel is correct in most turns at a track but on one or two bumps the forks will bottom. More air creates a softer longer curve while less creates a sharper more abrupt curve.

Heat is used during the vulcanization process to turn a very soft plyable rubber into a very durable and resiliant one by actually changing the chemical compounds in the rubber. This is done in a mold under very high pressure. Granted the heat used is higher, this is what is required to cause the chemical changes. After the vulcanization the tire is quite chemically different than it began, heat now acts difeerently on the newly formed molecules. And the forces acting on a tire on a motorcycle is very different than sitting in a static mold. Vulcaniztion Sorry to swipe your link, it appears we were researching at the same time. Kudos. Jim Allen is the US manager of Roadracing for Dunlop. That was a tongue in check suggestion.

But a voltmeter on the battery. Should have at least 12.25 with the key off. Turn the key on, if the voltage drops below 10.5 volts most electrial circuits will not operate, ie ECM. It is fairly common to have a battery loose one cell, but be still be able to be read over 12 volts, after a charge due to its surface charge. Appling a load will quickly drop the battery to its true level. Remeber that a light bulb (headlight) will illuminate with very low voltage, so that is not a very good indication of charge. Be very careful jump starting your bike. Most bike electronics do not take kindly to high voltage levels. Many starter / chargers can put out over 15 volts in starter mode, this can quickly fry expensive parts. Many car alternators can also put out 14.5 volts which I have seen cause problems also.