Another crank gone!!

[sanddune51]

I'm not convinced that the 900 and 850 pumps aren't exactly the same part.

They're certainly the same price on AJ Suttons website

Mark.

[misterdimwiddy]

I wonder whether the TDM900 runs at higher oil pressure then?

Maybe you could achieve this by altering the pressure relief valve in the sump of the TRX (p2-19 and 2-20 in the online manual). Shimming the spring or changing it may be possible but s'pose you would need a gauge on the system to see the effect of any change (+ temperature/viscosity affects on pressure to complicate things).

I recall doing something like this on my old RSC998 CB900F.

Looking at the diagrams it is not clear to me which of the two pumps the relief valve affects; you would think it would be pump #2 for motor lubrication; why regulate the pressure for the tank return?

Also noted that the gallery bolt in the head appears to be on the main pressure circuit (p2-22 fig A) , not simply gravity fed. Mine always trickled from here (low pressure?) when I thought it should have given me a good drenching when removed.

Doubt there will be many 900 pumps around especially if we are all looking for them.

It does, same amount (and i use TRX tank and pan) and the glass i over full at pressure. Those metal pumps really push way better!

KW - did you once post that you use a TRX sump to give clearance for Akra headers? TDM sump is deeper I recall (greater capacity) but if it's a dry sump who cares how big it is? Gotta be more flow and higher pressure (or different oil path meaning that LH rod is not at the end of the line)?

My guess is as goods as yours.

[Killerwhale]

I'm not covinced that the 900 and 850 pumps aren't exactly the same part.

They're certainly the same price on AJ Suttons website

Mark.

Same price OEM as well, TRX part: YA00129133 TDM part: YA00383383
What i can see is that the TDM part is of other metal.
What i´ve seen on my tdm lump is that the wheel itselve looks more like the one on R1

[sanddune51]

I don't know how badly the Trx pump wears (with reduced output being the result)?

I suppose what we are interested in is if the 900 pump delivers a greater volume and/or a higher discharge pressure. As we are talking about positive displacement pumps, then the 900 pump needs to be physically bigger to deliver a greater volume.

Does anybody have both 850 and 900 pumps to hand to compare them side by side?


Mark.

[misterdimwiddy]

Pics of crank damage sites for info;

Main bearing shell condition - not too clever really but don't appear to have suffered lubrication failure



Rod and spun shells - bit of discolouration of the rod and shells have had it



Big end journal - hardly any damage really; certainly no heavy groove wear as seen on big end journal



Main bearing journal - Worst damage of all; two deep grooves where shells contact the crank. Has to be high mileage wear I reckon with implications for low oil pressure



It's all scrap now but have all other engine parts including low mileage 878 JE pistons and barrels, a good head, cases, clutch..........may well end up flogging as a job lot or in bits. Watch this space.

[dixonj]

Phil, there is a tdm engine on eBay £150 buy it now or offer item number 181122445761 got to worth a shot to get u back up an running.

[misterdimwiddy]

Phil, there is a tdm engine on eBay £150 buy it now or offer item number 181122445761 got to worth a shot to get u back up an running.

I did see it mate. Thanks for pointing it out. There's another for £350.

Assume would be a 360deg crank not 270 but that wdnt bother me. If he'd go for £100 and then I add new shells and gaskets it would be feasible.

Would have to change CDi to get the right sparks and not much else I am thinking?

My fear would be whether the crank condition was up to track day riding (that's all I do now) with my other engine mods? It would be a risk that could go either way. To be certain of the crank I would want to split the cases and take a look inside I think. Would not want to build up my 878 top end and do another crank this year!

I am processing a few options currently and will add this to the mix.

Phil

[sanddune51]

I for one would hate to see the vultures picking over the bones of your Trx for the juicy morsels.

I think a 360 degree engined Trx would be a lot of fun and should be an option worth investigating. My old 878 Tdm on 41's is great fun.

Mark.

[Killerwhale]

I for one would hate to see the vultures picking over the bones of your Trx for the juicy morsels.

I think a 360 degree engined Trx would be a lot of fun and should be an option worth investigating. My old 878 Tdm on 41's is great fun.

Mark.

Just saw a crank on TRX.DE for 280€, just saying...

[dixonj]

I for one would hate to see the vultures picking over the bones of your Trx for the juicy morsels.

I think a 360 degree engined Trx would be a lot of fun and should be an option worth investigating. My old 878 Tdm on 41's is great fun.

Mark.

+1. Even if you build it up and sell it as a running bike.

[misterdimwiddy]

I for one would hate to see the vultures picking over the bones of your Trx for the juicy morsels.

I think a 360 degree engined Trx would be a lot of fun and should be an option worth investigating. My old 878 Tdm on 41's is great fun.

Mark.

Just saw a crank on TRX.DE for 280€, just saying...

Have you got a link to the site/item please KW?

Can't find it myself.

Thanks

[misterdimwiddy]

I for one would hate to see the vultures picking over the bones of your Trx for the juicy morsels.

I think a 360 degree engined Trx would be a lot of fun and should be an option worth investigating. My old 878 Tdm on 41's is great fun.

Mark.

You are right Mark.

I would of course need balance shafts as well as the CDi for the 360deg crank to work in my motor. These should be cheap and cheerful and readily available I would think.

[cycloneranger]

There is a TRX motor on evilbay at the moment. http://www.ebay.co.uk/itm/YAMAHA-TRX-85 ... 8669885%26
Has a bottom end noise, but if you intend to replace the shells anyway it could be an option. Did not sell last time so he might take an offer.

[zednine]

Different oil tank arrangement on the 3vd engine as well ........ more work as the 3vd doesnt have a piggy back oil tank like the 4TX ....... Im not sure they can be fitted at all

[Killerwhale]

Different oil tank arrangement on the 3vd engine as well ........ more work

http://www.trx850.de/phpBB3/viewtopic.p ... 13#p138213