Replacing 2000 ST1100 Water Hoses - Questions

jacMA

jacMA

Joined
Dec 30, 2022
Messages
50
Age
60
Location
Boston
Bike
2000 ST1100
Hi All,

Just finished the BOS to FL trip. In PA started a coolant leak right at the port to the expansion tank hose, from the radiator. Cut it, put it back on and went on my way knowing I had more work to do. While I was in there, I noticed coolant coming off the threads/liner of the right-side coolant hose coming from the thermostat, so I would imagine that I need to replace, and tightening the clamp won't solve it ;) ...but to finish the ride, I did tighten. So not looking forward to pulling everything and changing hoses. More than that I have a few questions:

1) At this point are OEM hoses from Partzilla even good, or would they be dry rotted? ...I do have two OEM, in package, right-side hoses from the previous owner.
2) Is there a non-OEM expansion hose I can get? specs?
3) I'm thinking that if I do this, may as well replace: the 3 hoses (two engine, one expansion), Carb boots, thermostat. Anything else?
4) Any tips, or articles about the process are welcome.

as always, thanks in advance!!

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I recently installed braided silicon hoses, and they fitted perfectly:

Fits for 1991-2002 Honda ST1100 Silicone Radiator Coolant Hoses Kit Replacement | eBay

Fits for 1991-2002 Honda ST1100 Silicone Radiator Coolant Hoses Kit Replacement | Vehicle Parts & Accessories, Motorcycle & Scooter Parts & Accessories, Engine Cooling | eBay!
www.ebay.at

Rest, like internal bypass tube, also with braided silicon line.

I'd also replace the radiator cap, likely the gasket on yours is already cracked...
 
Don't know about Partzilla but the Honda hoses I got from RonAyers were fine.
But I like Martin's deal with the silicone hoses a bit better!
You also need to check the water 'necks' under the carbs while you are in there.
Sometimes they will corrode and can cause seepage.
Not too difficult if you have the place to work and don't get in a hurry. ;)
 
When I changed my hoses years ago I recall that the OEM hoses took a lot of force to push onto the neck before tightening the clamp. I was used to hoses that slipped on fairly easily, and then secured with the clamp. The Honda hoses were much more tight fitting than others I had replaced over the years, and the job took longer than I expected because they didn't just slide right on, they took a lot of twisting and turning (and swearing). The short hose between the radiator and T-stat housing was especially tough to get seated.

I am curious if the silicone hoses are easier to install than the OEM hoses.
 
dwalby said:
When I changed my hoses years ago I recall that the OEM hoses took a lot of force to push onto the neck before tightening the clamp. I was used to hoses that slipped on fairly easily, and then secured with the clamp. The Honda hoses were much more tight fitting than others I had replaced over the years, and the job took longer than I expected because they didn't just slide right on, they took a lot of twisting and turning (and swearing). The short hose between the radiator and T-stat housing was especially tough to get seated.

I am curious if the silicone hoses are easier to install than the OEM hoses.
Click to expand...
I just replaced most of the hoses on an st1100 with oem. They were so tight that I wound up using some assembly lube.
 
ST1100Y said:
I recently installed braided silicon hoses, and they fitted perfectly:

Fits for 1991-2002 Honda ST1100 Silicone Radiator Coolant Hoses Kit Replacement | eBay

Fits for 1991-2002 Honda ST1100 Silicone Radiator Coolant Hoses Kit Replacement | Vehicle Parts & Accessories, Motorcycle & Scooter Parts & Accessories, Engine Cooling | eBay!
www.ebay.at

Rest, like internal bypass tube, also with braided silicon line.

I'd also replace the radiator cap, likely the gasket on yours is already cracked...
Click to expand...
English language link? I didn't see a 'translate'.
 
DeanR said:
English language link? I didn't see a 'translate'.
Click to expand...
Just enter the item number [323895674735] or the description [Honda ST1100 Silicone Radiator Coolant Hose Kit] into your search field...

Uncle Phil said:
Martin - Were the silicone hoses easier to install than the OEMs (just curious)?
Click to expand...
Inner diameter where a perfect, snug fit, a tad more wall thickness but the clamps still fitted nicely...
 
Does anyone know of any aftermarket silicone hoses that are not from China? FWIW, I have had enough poor experiences with Chinese-made product that I no longer willfully use it on my motorcycles. I've run SamcoSport on most of my bikes for many years, but they do not have an application for the ST.
 
DesmoRonin said:
Does anyone know of any aftermarket silicone hoses that are not from China?
Click to expand...
I read you...
I'd mulled over them for over a year, but couldn't locate any other maker...
I know that its an experiment, but I got curious and couldn't resist the price (vs OEM) either...
The vendor at eBay offers a vast selection for various car models, etc... and have top customer feedback throughout...
 
Anyone know the Specs (I.D. and length) of the expansion tank hose...the one from the radiator?
 
ST1100Y said:
I read you...
I'd mulled over them for over a year, but couldn't locate any other maker...
I know that its an experiment, but I got curious and couldn't resist the price (vs OEM) either...
The vendor at eBay offers a vast selection for various car models, etc... and have top customer feedback throughout...
Click to expand...
Thank you for the input, but I'm not sure if I'm willing to let down my guard over performance parts from China yet. Lost confidence is a hard thing to regain.

I'll contact SamcoSport and see if they will be willing to make up a set with a certain minimum order, and maybe some interested parties here would be willing to help me meet that order for a reduced price.
 
jacMA said:
Anyone know the Specs (I.D. and length) of the expansion tank hose...the one from the radiator?
Click to expand...

The noun nomenclature for the bulk hose part number listed in the link in post #11 above shows an ID of 5.5mm. Dunno the actual length on the ST, but you can measure yours. Add a few extra inches for good measure when you buy off a roll locally. HTH

John
 
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John OoSTerhuis said:
The noun nomenclature for the bulk hose part number listed in the link in post #11 above shows an ID of 5.5mm. Dunno the actual length on the ST, but you can measure yours. Add a few extra inches for good measure when you buy off a roll locally. HTH

John
Click to expand...

...I was talking about the hose from the radiator cap/thermostat to the expansion tank. That said, I do see that the next line in the description says 8mm, so I thank you sir!

Okay, reading other posts, one says 5.5, another 8mm, so I guess I'll go back and take a caliper to the metal nipple coming from the radiator/thermostat housing. I know I have to take it apart anyway, but I was just looking to do it in one sitting.
 
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I can’t help you with the the measurement but I change mine a few years ago and used auto transmission cooling hose. It is robust and will take the heat cycles.
 
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