Repsol Idle Screw

[axulsuv]

Billy ; We need to do a little research on how honda's (I believe, speed density system ) responds to inputs ...

It should ? be as simple as adding a resister or two to the system to fool the ecu ... But you would have a fat ole pig in normal conditions ...

And is there anyway to adjust the fuel pressure at the regulator ? More pressure at the same pulse width at the injector will feed a tad more fuel .

And my buddy's bike is also 300cc I think ...

Maybe Biff will chime in , being Blue oval guy he should be familiar with this setup , and how to hot rod it ....

Glenn ,

And where are you riding that overcomes the factory MAP ??? Honda wants to know ?

I used to live in So. Cal. so I am curious what area is defeating your bike ....

[billyt]

Glenn

I was riding an event approximately 50 miles NE of Payson AZ in the Tonto National Forest area.

The bike was running great up until that event. May as well have been Everest as I could not breath LOL

I kept expecting to see a Sherpa (no, not a trials Sherpa bike) at the section with water and a oxygen bottle and offer to ride my bike to the next section for me LOL

I am not going to be drilling holes in my fender to let more air in. I have changed to a one step hotter plug, removed the back flame guard, cleaned out my air filter, re-checked my RPM to 1875. Re-route any and all breather hoses going into the air box.

I will be back riding normal altitudes (2000 > 3000 ft) this weekend so we will see how she rides. She ran great at those heights prior.

One other suggestion I received was to try running Race gas for high altitudes. What do you think? Do you think race gas at altitudes has the same effect on a FI bike as it would on a normal standard carb bike? Will running race gas harm the FI injectors. Cope, BR40t please chime in on this question.

Thanks

Edited September 5, 2014 by billyt

[b40rt]

" Race gas for high altitudes. "

biilyT

​Don't know anything about this, however if you want any info on cheap brass jets let me know.

[axulsuv]

Ave gas or race fuel should be a plus at any altitude and is better for anything to due with fuel injection , if you had fuel with ethanol in it that would only make matters worse , And the hotter plug may have been a step in the wrong direction , as I thought you stated the plug was white-ish ? If it's not sensing enough air flow / density the ECU will back off on fuel to prevent a rich condition . I haven't had a chance to look at a schematic yet , but does the honda have a O2 sensor in the exhaust ?

Glenn

Edited September 5, 2014 by axulsuv

[axulsuv]

Ok , I looked at the PDF...

Very basic Programmed ! fuel injection ... Non feedback -(no O2 sensor) . It has definite limits in adaptability ...

I know you don't want to hear it but , your best bet , safest bet , Maybe a dual map programmable throttle body/ecu .

And if we add a resister to the TPS (not the idle switch in it ) to make the ecu think throttle opening is less than it actually is ie. allowing more in , It is just gonna conflict with map and iat sensors and rpm and may put the system into a limp mode or it could work fine if a small enough change on the input is made . Could be a expensive experiment ...

I'd be willing to bet that the works bikes are mapped out with a gas analyzer to achieve the correct

stoichiometric for the up coming conditions , and they may have O2 sensors and exhaust gas temp sensor's too , for alot better control and range of the efi ...

So apart from changes on the airbox side to increase volume and velocity , which may have adverse effects @ sea level , I think some reprogramming is your best bet ...

Glenn

But get some ave gas at least for your mountain trips ... It's a good thing.

And here is a article that may help you see what is going on , and the limits of honda's pgm . It only has limited response's within a fairly narrow window of inputs . http://tunertools.com/articles/AFR-Tuning.asp

Edited September 6, 2014 by axulsuv

[guys]

John suggested running a hotter plug i.e CR5EH-9. The bike comes standard with a CR6EH-9

I will follow the advice of running one step hotter plug (#5 instead of a #6) along with trying to get more air flow into the filter box.

My Montesa dealer advised me to use the CR5EH-9 plug in colder conditions, at temps below 10°C, quite the opposite of what you where riding in.

John may have had his reasons for his suggestion, but logic would rather dictate to go the other way. Just my two cents, I could be wrong.

Edited September 6, 2014 by guys

[axulsuv]

Well I'm loading me & the kid's bike's and gear for a event in NC. tomorrow , gotta lube chains & check oil , etc.....

Good Luck Billy , I'll talk to my buddy for ya, and see if he has any more insights .

And yippee ! it's raining

Glenn

[axulsuv]

Billy it turns out you most likely know my Irish Friend and have ridden with him in the past ... Lost in the NC. woods ????

And is your bike a Canadian or a US market bike ? I'll pm you when I get a chance ...

Glenn

[mags]

Some info on heat range...

Mags

The insulator nose length is the distance from the firing tip of the insulator to the point where insulator meets the metal shell. Since the insulator tip is the hottest part of the spark plug, the tip temperature is a primary factor in pre-ignition and fouling.

Whether the spark plugs are fitted in a lawnmower, boat, or a race car, the spark plug tip temperature must remain between 500C-850°C. If the tip temperature is lower than 500°C, the insulator area surrounding the centre electrode will not be hot enough to burn off carbon and combustion chamber deposits.

These accumulated deposits can result in spark plug fouling leading to misfire. If the tip temperature is higher than 850°C the spark plug will overheat which may cause the ceramic around the centre electrode to blister and the electrodes to melt. This may lead to pre-ignition/detonation and expensive engine damage. In identical spark plug types, the difference from one heat range to the next is the ability to remove approximately 70°C to 100°C from the combustion chamber. A projected style spark plug firing tip temperature is increased by 10°C to 20°C.

Also... for altitude...

Barometric pressure/Altitude’

Also affects the spark plug's tip temperature

The higher the altitude, the lower cylinder pressure becomes. As the cylinder temperature decreases, so does the plug tip temperature

Many mechanics attempt to "chase" tuning by changing spark plug heat ranges

The real answer is to adjust jetting or air/fuel mixtures in an effort to put more air back into the engine.

[axulsuv]

Billy I tried to PM you all the pertinant info you need , but your box is full and the message is off in cyberspace now ...

CLEAN YOUR BOX !!!!

Glenn

[billyt]

Glenn

Try: williamtraynor@hotmail.com

Thanks

[tman427]

Hi Guys

and#160;

Some more info.

and#160;

You can see by the attached PDF file at the bottom that the idle screw (7) is in fact a not a hard mechanical butterfly throttle body stop but rather a air by pass orifice.

and#160;

It affords an air adjustment from the filter side past the butter fly to the throttle body at idle.

and#160;

If this is true you can then assume that the idle screw definitely only adjust the idle RPM which is necessary 

for good starting amperage/voltage.

and#160;

I am using a Jitsie filter currently.

and#160;

The idle is sitting at 1875 RPM checked with a Snap On Automotive Digital RPM meter.and#160;

and#160;

John suggested running a hotter plug i.e CR5EH-9. and#160; The bike comes standard with a CR6EH-9

and#160;

I will follow the advice of running one step hotter plug (#5 instead of a #6) along with trying to get more air flow into the filter box.

and#160;

JSR Hunt what do you mean by "It may also be worth removing the head breather pipe from the airbox just to get that little bit extra clean air into the system”.

and#160;

Apart from that I guess it is all in the ECU and mapping as it looks at air density, temps, altitude etc and then goes through its algorithm accordingly supplying fuel.

and#160;

I guess it was a perfect storm of high temps, stagnant air flow in the woods, high altitude, and dry dusty conditions.

and#160;

This is a direct quote out of the 2014 Montesa manual and#160;

and#160;

"Start Up Recommendations: and#160; If using your motorcycle at different heights, bear in mind that you must adjust the idle; otherwise you may have problems operating the vehicle”.

and#160;

So they want you to adjust the idle at higher altitudes, partly due to starting and idling and off idle. and#160;

and#160;

and#160;

and#160;

That coupled with my bad throttle and clutch control did not help.

and#160;

The bike starts okay at sea level. and#160;It is also a 2014. and#160;Could the valves need adjusted already?

So quick question here...which way to get a faster idle, turn the idle screw to the right or left?

[sportsawyer]

So quick question here...which way to get a faster idle, turn the idle screw to the right or left?

 

CCW to increase idle speed.

 

[Rollox]

For those boys who are playing with the idle screw 10 times a day:

http://www.vitititaniowtc.com/en/motorcycle-accessories-parts/light-part-ddm-prodotti-per-moto-trial.html

 

"New ergal regulations minimum without tools for Montesa 4RT. Weight 7 gr.", about 16,- EUR

 

Attention: there is no O-ring included and Montesa don´t sell it separate.