Benelli Forum banner

1 - 12 of 12 Posts

·
Registered
Joined
·
75 Posts
Discussion Starter · #1 ·
Benelli TNT up and running here in Saudi, but there is a problem. It is hot here, very hot, with ambient 40'C.

Went for my first ride and most things OK apart from dodgy speed reading (random I think would be correct), and well squared off tyres (shame on you RED DOG for not telling me they were worn and the speedo was dodgy).

But worst of all I stopped to fill up with fuel on the way back after a 30 minute blast. When I tried to restart, it was if there was no juice in the battery and it really struggled to turn over. On the 5th attempt, and just as I was gonna give up it suddenly caught and started. But this is not a worry, as case I am miles form nowhere and it gives up. I left the bike when i got home for a hour and then it started first time :confused:

IS this the HOT START problem, my last TNT wasnt like this at all, just started, stopped and behaved generally, although I rode it in the UK only. More to the point what are the solutions - bigger battery ? some factory upgrade? move somewhere colder?


Cheers for your help. I may be a far more common(maybe I mean regular) member of the site now - as the nearest dealer is in......... well there isnt one for about 2000 mile, so it is left to me, the Workshop manual, and you lot from the site who are far more useful than the manual :bow:

Thanks to those that gave the info on the wheel removal - Abba stand on order, along with some new tyres, cant wait to see what they think of that as hand luggage :D
 

·
Super Moderator
Joined
·
7,770 Posts
Hi Ian,

This seems to be quite a common problem particularly with the newer TNT's. I had a test ride on a Cafe Racer when my TRE was being serviced last year, pulled in to fill her up with petrol and the bugger wouldn't start again.

After calling KJM to tell them I was stranded with their demo bike in Asda's filling station I was advised to just leave it for 15 mins before trying to start it again and what do you know, it bursts into life again.

I'm sure you'll find some info on this problem if you search through the TNT Forum though.
 

·
Registered
Joined
·
332 Posts
hot re-starting

Hi

I've had the air temp sensor moved from in the airbox (just above the head) to under the top yoke. I think new bikes have this as standard. Apparently when the bike is hot and you stop it, the temperature in the airbox goes through the roof and confuses the ecu - after a little while it cools, and the bike starts fine. Also there's an upgrade to the starter motor which might be available under waranty - waiting for that to come in. Finally you will see elsewhere people recommend doubling up the cables from the battery to the starter motor, as they are under-rated.

Good luck - it's worth sticking with it, great bikes.
 

·
Senior Member
Joined
·
5,896 Posts
Doubling up the cables on the TNT makes a big difference to it spinning over.
Although it is better, the improvement is not as pronounced on the 900.
 

·
I'm firing on three
Joined
·
611 Posts
Hi

I've had the air temp sensor moved from in the airbox (just above the head) to under the top yoke. I think new bikes have this as standard. Apparently when the bike is hot and you stop it, the temperature in the airbox goes through the roof and confuses the ecu - after a little while it cools, and the bike starts fine. Also there's an upgrade to the starter motor which might be available under waranty - waiting for that to come in. Finally you will see elsewhere people recommend doubling up the cables from the battery to the starter motor, as they are under-rated.

Good luck - it's worth sticking with it, great bikes.

mmmmmm interesting, if what you say is true maybe the factory have read my correspondences concerning the thermistor, if they then do the ignition timing mod on the mapping I think we will then have the 1st reliable italian bike......... :ele: :ele:
 

·
Senior Member
Joined
·
1,841 Posts
Air Temp Sensor

This talk about the enterance air temp sensor has got me thinking!
The sensor is close to the intakes because that is the temp of the air entering the engine at any time. If the engine is stoped and the engine heats the air in the air box, the ecm must trim the fuel to match the temp of the air it intakes. Moving the sensor to the front of the bike is only giving false data to the ecm.When you are doing 150mph the air at the sensor in the airbox will be cooler and the ecm will trim the fuel richer. when going slowly the airbox will be warmer and the sensor will give data to the ecm to lean the mixture. Moving the sensor will therefore give incorrect fueling most of the time !
If there is a fault it must be the program,perhaps if the thermistor goes past a certain temp/resistance the ecm outputs incorrect fueling? It cerainly is not a good thing to place the thermistor at a point where it is not measuring the air it should be! Thats a bit like putting your central heating thermostat in the garden!
By the way Terry did you see my post a while ago? the tre does fire up on a after tdc ignition. Not sure if the walbro does though:confused:
 

·
I'm firing on three
Joined
·
611 Posts
No I missed your post Colin? but that’s even more interesting it looks like they are thinking on the same lines as us, I will try and find out if the maps are the same for the TNT range……….. ref the thermistor whilst I understand your logic with respect I think there is a slight flaw, the fuelling and ignition are modified by the ECU as a result of different signals being received from sensors on the engine (tps,air sensor,rpm etc) now the air sensor (thermistor) should be/is calibrated to register ambient air entering the airbox (not engine temp). This info as a resistance is then registered by the ECU.
with an engine reaching 100deg + less than 40mm away from the thermistor and no cooling airflow over it (when the bike is stationary) the thermistor will be heated via radiated heat and will be fooled into thinking the ambient air temp is higher than it really is, the fuelling is then modified incorrectly by the ECU to compensate, and until the thermistor cools down the bike runs badly (or doesn’t run as the case maybe) that is why I think repositioning the sensor makes such a difference. last year I replaced my thermistor with a ten turn pot (I soldered a resistor between the wiper and feed to drop the range and cope with the supply voltage) when the bike was well and truly hot I adjusted the pot which fooled the ECU into thinking the ambient air temp was changing, you could hear and feel the difference in how the engine was running. I eventually took it off and moved the thermistor to a more suitable place and found the bike was far more consistent with the way it ran.
mmm rambled abit sorry :eek:
Terry
 

·
Registered
Joined
·
113 Posts
air temp sensor

The air temp sensor on 2006 models onwards, TNT, Tre-K etc has been fitted to the inside of the cockpit fairing to gain a true air temp and improves running due to being away from engine heat/debris build-up in the airbox. In this position the sensor is reading still air at the correct temp this improves the fuelling across the whole rev range :)
 

·
Senior Member
Joined
·
5,896 Posts
Maybe a solution to the stationary temp sensing, for those with the sensor inside the airbox, would be to add a heat shield to the outside of the airbox. This would simply be high strength aluminium foil, glued to the outside with dobs of hot melt glue. The glue would give some airspace between the box and the shield, improving the insulation. The foil would reflect radiated heat.

Worth a try?
 

·
Senior Member
Joined
·
1,841 Posts
I have looked at my tl1000 intake air temp sensor and it is fitted on the side of the airbox, also I checked the triumph 955 manual and the sensor is fitted on the top of the airbox. It seems the Benelli problem is its position,so moving it to the top of the airbox may be an improvement? The ambient air temp behind the cockpit is not going to be the same temp as the air enterance temp. Right i am going to shut up now ! My RS starts first time anyway !:D
 

·
Registered
Joined
·
75 Posts
Discussion Starter · #12 ·
Hot Benelli

Thanks for the info and advice.

It is a 2004 benelli, and I ma gonna try the air box move as a start, and was also gonna look at coveringh the battery compartment with heat ducting to protect the battery from overheating so csn apply same principle to air box.

Despite being one of the largest countries in the world, getting stuff here is a nightmare if it is not a standard american or japanese part

I will let you know what happens

Thanks
 
1 - 12 of 12 Posts
Top