GT500 Broken Oil Line/hose, need replacement options/ideas

[Nicholas]

Hi All,
One of my oil pump lines has broken from my GT500, and it seems that NOS replacements are no longer available/easy to find.

I've been searching for:
16820-15033 (13), 16840-15033 (14), 16810-15131 (10), my #14 line is broken.
http://www.ozebook.com/compendium/gt500 ... arts85.htm" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;

Now I might be able to repair mine, but I was thinking that perhaps it might be easy to just create one from new parts.

Anyone done this before and or can recommend the bill of materials to do this?

I am not with my bike, but I do recall the tubes had narrow inner diameters...I am not sure I'll be able to match these...but is the pressure important? i.e. if I used larger inner diameters then the pressure would drop...or would it?

Any advice or links to places where new ones can be bought would be most appreciated!

[Nicholas]

I looked into making my own lines and thought I would share....

Now, if the banjo fittings can be salvaged then you can get by with using some new tubing and fittings. I have found that mountain bike disc brake banjo fittings come in the smaller M6 bolt sizes and so there are plenty of options here...

The trouble is finding the right check valve and pressure relief. I haven't spent time looking into if pressures are different from a pump perspective, so if someone has insight please share. I am assuming that the pressures will be standard across two stroke check valves and going out on a limb to think that you could use something from a Yamaha...

The following part number is for a inline nozzle fitting from an RD350 that seems to still be available via ebay and some stores.
353-13572-09-00

The following describes the GT500 oil lines
http://www.oldjapanesebikes.com/1977_GT ... l#Oil_Pump" onclick="window.open(this.href);return false;


And this analyses the check valve pressure for a Kawasaki, but I think it is similar to the Suzuki one.
http://kawtriple.com/mraxl/checkvalves.htm" onclick="window.open(this.href);return false;

If anyone has more information on the subject please share as I am sure there will be others who will benefit from this topic. Would be good to collect a list of suitable tubes, seals and bolts.

[citizenbanana]

Hi, Realize its an old thread but how did you make out? Have a similar issue...Can't find #14 replacement. Cheers

[dollydog]

i use this. 4mm o.d. i've build oil lines for my gt250 and these are the same sized tubing
cheers, dd.

4mm clear:
https://www.ebay.co.uk/itm/METRIC-IMPER ... SwxH1T46A8

[gammakeith]

As Dollydog says there is no need to use rigid fuel lines. Pretty much all 80's bikes use flexible pipe and the design of the pumps is pretty much unchanged. As well as Nylon, you can also use the Tygon tubing used by model makers for fuel lines. It has thick walls, a small bore and is much more flexible than Nylon. It seems sensible to select tubing that will be close to the original bore though unless its too outrageously different it should not make any difference to a positive displacement pump. Most RG500 owners have switched to Tygon along with in-line Yamaha check valves (the originals in the carburettors fail). When I got it, my T20 had been modified to use flexible hose but it was in a right state so I switched to Tygon lines. I had to use some minature tubing adapters connecting to larger Tygon tubing stubs to fit the spigots. The original Suzuki check valves (part of the bolts into the crankcase) feel like they have a much higher "crack" pressure than the more modern Yamaha valves with a "blow" test so I don't see the pumps struggling with anyone using those for a conversion.

Keith

[citizenbanana]

Thanks guys!

[jabcb]

Do you have the part number for those modern Yamaha check valves? Or aftermarket source?

[MalkyB]

Hi guys. I find myself in a similar situation. I can see the flexible nylon tubes on eBay but how can I connect the tubes to the valves either end - will the push-fit connectors work...???