New thermostat in hand

Blrfl

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I love my simple carbureted 1100!
Carburetion is arguably more mechanically-complex than fuel injection and, based on what I see in Carb Talk, isn't exactly a paragon of being problem-free, either. It's also a ham-handed way to fuel an engine since any jetting configuration is a compromise with no way to compensate for changes in pressure, temperature or ignition timing while the engine is running. Don't even get me started on what a nightmare it becomes when trying to keep a lid on emissions.

A stuck-open thermostat on an 1100 will cause just as many problems as it does on a 1300. An engine running cool with an intake system set up based on the assumption that everything's up to temperature isn't going to come anywhere close to fueling the engine ideally. If you compensate for it manually with the choke, you're burning more gas. Meanwhile, in 1300 land, the fuel injection system is doing exactly the same thing because it wants the engine running at the correct temperature. Where the two diverge is when the rider twists the go-fast knob. The carburetors in the 1100, which are totally ignorant of the fact that the engine isn't up to temperature, will continue fueling the engine in an off-nominal way and the rider, not getting full smoke out of the engine, will twist it a bit harder to get what he wants. Meanwhile, the 1300's FI system, which is aware of its surroundings, can supply a mixture that's ideal for conditions during acceleration and go back to running rich during cruising to try and pull the temperature up.

Overall, FI is a much more complex process than carburetion, but the additional complexity results in better fueling and a healthier engine that will last a lot longer. The physical parts of the system that are more complex are also a lot more reliable because they're not mechanical and don't require adjustment. The 1300's FI system has twelve types of things that can go wrong, none of which will leave you with an fully-functional motorcycle. The remaining three (loss of connection to the cam or ignition pulse generators or a fuel injector) result in a no-run condition. For any of them, the ECM will tell you that there's something wrong exactly what it thinks is wrong in less time than you'd spend scratching your head over what might be wrong in a carbureted system. I don't miss that stuff a bit.

--Mark
 
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DavidR8

DavidR8

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Does partzilla not ship to Canada? I paid under $30 for my thermostat and ended up getting odds and ends to add up to over $100 So I got free shipping(free shipping may only be for US shipments).

Sent from my SM-G955U using Tapatalk. Here is a screenshot of the parts list for you 05. .

Partzilla does ship to Canada however once currency exchange, duty and shipping are taken into account it's basically the same price.
The part is $29 USD plus $8 USD shipping for a total of $37 USD. Conversion will run 25% at best so that takes it up to $45 CDN. Duty and brokerage fees will add a few more dollars so $53 is about right.


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Partzilla does ship to Canada however once currency exchange, duty and shipping are taken into account it's basically the same price.
The part is $29 USD plus $8 USD shipping for a total of $37 USD. Conversion will run 25% at best so that takes it up to $45 CDN. Duty and brokerage fees will add a few more dollars so $53 is about right.


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Ouch. . I've ordered things from the UK before(centre stand for my F4i and other parts not available in the US) and it actually work out the other way for me. I actually saved just because I don't have to pay the stupid VAT.

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DavidR8

DavidR8

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The third bar lights up around 150 deg. F and the fourth bar lights up around 230 deg. F. That is a range of 80 degrees F in which you see the same three bars on your temperature gauge but you really do not know what the engine temperature is within that range. (Oh-no! I just opened us to another shot at the 1300 from Bush). If your engine is constantly running at the lower end of this range it certainly would negatively affect your MPG- whether it will affect it to the degree that you are seeing is another question. The only way to rule out the thermostat is to make sure that it is operating correctly or to replace it with one that is known to be good- I would bench-test the new one before I put it in. Bench-test the old one just for kicks and let us know what results you get so we'll know if this is a big influence on MPG.
I’m going to bench test both I think.
This is a shot of the new thermostat coming out of boiling water (212 deg f). It is fully open. See the video below to watch it close. Scintillating stuff!


Here's a link to a 40 sec video of the thermostat closing.
It closes rather quickly as it its going from boiling water to ambient air. I expect that in place the changes would be much slower.
https://youtu.be/byjJEwk6IEU


One thing I just remembered. In the morning about 5-7 mins after I leave my house I make another stop for about 30-40 mins. When I stop the gauge shows three bars. When I come back after 30-40 mins it's never at three bars, it's at two bars. So this leads me to believe that it's barely into the three bar temp range after 5-7 mins.
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Watching a thermostat close is probably as exciting as watching paint dry. The end result is what's important.
 

Blrfl

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One thing I just remembered. In the morning about 5-7 mins after I leave my house I make another stop for about 30-40 mins. When I stop the gauge shows three bars. When I come back after 30-40 mins it's never at three bars, it's at two bars. So this leads me to believe that it's barely into the three bar temp range after 5-7 mins.
That's a good possibility.

The problem you're looking for isn't a thermostat that opens fully, you're looking for one that doesn't close all the way at room temperature. That causes coolant to flow through the radiator when it shouldn't and pulls the engine temperature down. Most of us with early copies of the 1300 are prone to this problem; I think they had it pretty much licked by 2007 or 2008. There might just have been a big batch of bad thermostats or, as some have theorized, paint overspray or some other goop collected on the slug and caused it to drag, which was certainly the case with mine:

goop.jpg

The acid test for this is to go out on a day when the temperature is at or below about 6°C and ride at freeway speeds. If your thermostat is stuck open, you'll see the third bar flicker or go out entirely. But if you've got the plastic off, it's easy enough to just pull it out of the housing and see what state it's in.

--Mark
 
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DavidR8

DavidR8

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That's a good possibility.

The problem you're looking for isn't a thermostat that opens fully, you're looking for one that doesn't close all the way at room temperature. That causes coolant to flow through the radiator when it shouldn't and pulls the engine temperature down. Most of us with early copies of the 1300 are prone to this problem; I think they had it pretty much licked by 2007 or 2008. There might just have been a big batch of bad thermostats or, as some have theorized, paint overspray or some other goop collected on the slug and caused it to drag, which was certainly the case with mine:

goop.jpg

The acid test for this is to go out on a day when the temperature is at or below about 6°C and ride at freeway speeds. If your thermostat is stuck open, you'll see the third bar flicker or go out entirely. But if you've got the plastic off, it's easy enough to just pull it out of the housing and see what state it's in.

--Mark
Gotcha!
The fully closed at room temperature part is the essential bit!


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Never saw a thermostate at work before, very interesting. David, I hope you find the cause of poor mileage and share with us. My guess is nothing wrong with your thermostat. Does your rad fans come on and off? I think it is the winter gas. I used to get bad mileage when I was riding in the winter time. Kenny
 
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DavidR8

DavidR8

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Never saw a thermostate at work before, very interesting. David, I hope you find the cause of poor mileage and share with us. My guess is nothing wrong with your thermostat. Does your rad fans come on and off? I think it is the winter gas. I used to get bad mileage when I was riding in the winter time. Kenny
Thanks Kenny,
Yes the fans do cycle on and off.
I'm reserving judgment on whether or not the thermostat will fix the problem. But I have to believe that I can get better than 22 mpg in the city.


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22mpg is like 9.3km per litre. It is gazzling a lot of gas. I just picked up my ST from the repair shop. Replaced all hoses and clamps in the aybass, rebuilt water pump, replaced thermostat while they were in there. Also installed a Turbo Tom fuel reg #58, and did a starter valve Sync. Going for a ride tomorrow and I'll let you know my gas mileage. Putting the ST away after tomorrow.
Thinking about the TT fuel reg, may be the previous owner of your bike had TT # 61 reg installed to match K&N filter and after market pipes. When he was selling the bike, he returned the bike to OEM filter and exhaust, but left the larger fuel reg. The bike will run rich. I am just guessing. That's what I was doing before spending the money to fix my ST. Now I am keeping the ST.
Kenny
 
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DavidR8

DavidR8

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22mpg is like 9.3km per litre. It is gazzling a lot of gas. I just picked up my ST from the repair shop. Replaced all hoses and clamps in the aybass, rebuilt water pump, replaced thermostat while they were in there. Also installed a Turbo Tom fuel reg #58, and did a starter valve Sync. Going for a ride tomorrow and I'll let you know my gas mileage. Putting the ST away after tomorrow.
Thinking about the TT fuel reg, may be the previous owner of your bike had TT # 61 reg installed to match K&N filter and after market pipes. When he was selling the bike, he returned the bike to OEM filter and exhaust, but left the larger fuel reg. The bike will run rich. I am just guessing. That's what I was doing before spending the money to fix my ST. Now I am keeping the ST.
Kenny
Thanks Kenny
I did pull the K&N. I don't see any evidence of different pipes; no marks on the hanger bolts etc though I only guessing.

Is a different fuel pressure regulator visibly obvious?


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No, Turbo Tom engraved a number eg 58, 61 on the side of the OEM fuel Regulaters that he converted. I think the numbers represent the PSI, OEm is 50PSI with no markings. I had Delveric pipes, I took them off a couple years ago, you cannot tell on the bike that they were ever there. i am selling the Delveric.
Kenny
 
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Not trying to sell them to you, just a side note. Worth taking a look at the fuel reg. I think you were just in there when you had the FI flashes. Lets put it this way, at stock form, my ST throttle was very jerky at low speed, needed a lot of clutching. Slow speed was a chore for me. I already felt the difference with TT fuel reg just driving the bike home from the shop.
If you find your slow speed throttle is smooth and well behaved, then there must have been an upgrade.
Kenny
 
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DavidR8

DavidR8

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Not trying to sell them to you, just a side note. Worth taking a look at the fuel reg. I think you were just in there when you had the FI flashes. Lets put it this way, at stock form, my ST throttle was very jerky at low speed, needs a lot of clutching. Slow speed was a chore for me. I already felt the difference with TT fuel reg just driving the bike home from the shop.
If you find your slow speed throttle is smooth and well behaved, then there must have been an upgrade.
Kenny
Oh sorry if I misinterpreted your mention of the Delkevic mufflers. Definitely wasn't my intention.

Interesting that you mention the pressure regulator. My ST is very smooth at low speeds. After I tightened up the throttle cable, low speed control improved tremendously.
I'm going to do a starter valve sync when my carb tune arrives so I will have a look at the pressure regulator then.


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Well, I'll let you know my gas mileage tomorrow after the final ride of the season and first ride with the TT fuel reg.
Another side note, I just sold my Morgan Carbtune 4 to another ST owner in US. Never used it, I thought I could do the work, but never had the confidence to do it myslef without an experienced helper. Now I just let the repair shop do it. My mirrors and wildshield don't vibrate anymore at idle. Happy hour time now, catch you later.
Kenny
 

ST Gui

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DavidR8 said:
I’m guessing you don’t ride through winter?
What's this 'winter' of which you speak? :rolf1:

I freely admit I don't ride in wet weather though that hasn't been a problem here of late.
 
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DavidR8

DavidR8

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Riding in the rain can be a drag but I have to say that compared to riding in the rain on my Tiger, riding in the rain on the ST is a dream!


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