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Discussion Starter · #1 ·
Hi guys,
I am fed up with the weakness of the turbo oil inlet hose. I've replaced it multiple times over the last few years, and it keeps failing. ObviouslyI experimented with different types of hoses and insulation materials, as well as clamp types. I am not sure why this is. I suspect it has to do with the hot climate I live in (Israel) and the fact that my home is located at a peak of a mountain, and I use a lot of Turbo boost climbing it up, and then shutting off the engine while its extremely hot.

Anyways.. I noticed my wife's car keeps the radiator fan working after engine shut-off. It happens even when the coolant temp is well below the fan-on threshold. I am thinking that the ECU is smart enough to figure out that the turbo had been working hard just before the engine-shut-off, and thus it keeps the fan running in order to cool down the turbo itself (and the oil in and near it). I am thinking of building a similar mechanism for my CX500TC. It doesn't have to be fully automatic - but rather just a timer that I can manually kick-off on shut-down and it would keep the fan running for 30sec to 1min.

What do you guys think about it? does it make sense? has anyone tried something like that?
and besides that - do you all suffer from that oil inlet hose going bad, or is it just me?

Thanks,
Oded
 

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1982 Honda CX500 Turbo
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I had a similar story. The advertised performance of the hose material was false and I experienced immediate failure. I followed Dutchtubo's advice and ordered 5mm Gates 3225 hose which is a Euro spec material. I also went back to spring clamps which expand and contract with temp changes while keeping a constant clamp load- which is what all OEMs use. No screw clamps. Use the most robust/tightest units you can find.
My failures were not related to heat coverings. I used the same material on my final solution as my first- its the hose primarily. Yes, use a good heat covering!- but the hose is the culprit here. I have 2300 miles on the bike since the last repair and its bone dry now.. I also ride the hell out of my turbo- that's what its built for. Shout out to Dutchturbo for the solution!馃挭

Tthe original thread that solved my issue is below. One item of note is that the space this hose lives in is VERY small! The possibility of AN fittings, etc is impossible given the space. Different high pressure/ racing solutions just will not package in this design unless some serious changes occur. A 2 inch hose is hard to industrialize! Yes, its a crap design from Honda. But we are all living with it :)

Just my .02 her based on my personal experience. Other solutions may exist that are more robust. Let's hear from the other forum members :)


Final solution before adding heat covering(for clarity)
Motor vehicle Hood Automotive tire Vehicle Automotive exterior
 

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I have been preaching about people using the wrong hose for years. You do not need an expensive high pressure hose, especially not a braided steel hose. You want something that can handle 100 psi, not 1000 psi. Temp wise, 300F would be fine. Getting the proper fit with the hose to the inlets is critical. In the US metric hose may be an issue, as you want the tightest fit possible. The spring clamps that Elrod refers to are much better than screw type hose clamps. They tend to go square as you tighten them this small. Another option would be small fuel line clamps, but the squeeze clamps are the easiest in the tight space around the turbo.
 
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On a side issue relating to the original post, when u you are switching off the motor after a hot run, its a hood idea to let it idle for a short time, maybe a minute, before switching it off. Lets cooler oil flow through the turbo bearings to bring the temp own some.
 

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1981 CX500C
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Small modification to Swiftnick......let the bike idle for about 5 minutes before shutting off after your climb.

Heat takes time to dissipate. One minute will help, but not much heat will be rejected in that minute.
 

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With turbos I always understood the reason to let idle a minute or so after running hard was more to let the turbo slow down. When shut off right away the turbo keeps spinning for some time without any oil flow which is hard on the bearings. I don鈥檛 think it is much of a temperature thing. Letting it sit and idle for 5 minutes is way overkill and I don鈥檛 recommend letting any bike sit at idle for that long.
 

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1981 CX500C
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Do as you wish with your ride.

I've got 2 rides with turbos. Each recommend an extended idle after a hard run to dissipate the heat. The heat in the turbo will cook the oil leading to oil coking. 1 minute won't dissipate much heat.

Try this simple experiment. Heat some water to boiling (212 F or 100 C). Take it off the heat, place the pan in a sink full of hot water for 1 minute, measure the temperature. Record the temperature. Now repeat the experiment, but this time place the pan in a sink full of hot water for 5 minutes. Measure the temperature. Record and compare.

The temps in a turbo greatly exceed boiling water. You decide which is a better path.
 
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