Yamaha TRX850 Enthusiasts Forum

Hi all. I have had my 95 TRX for a couple of years, but up till now it has just been a shed ornament because when I purchased it from a mate way back when I was told it had an engine nock, which I thought I would just strip it down and replace the required parts and put it on the road. The bike had been well looked after externally by the original owner, but as I was also told it was shut down straight away when the engine nock started, and the bike trailered home, (bullsh1t) I found the crank and one rod flogged out, with only the smallest part of the big end bearing left. After a year or two of searching for reasonably priced replacement parts, I worked out that replacement crankshafts and rods are as rare as rocking horse shit. I finally found an almost complete 98 model for $450. I have managed to fit the engine in to my bike but I am having a bit of trouble working out where all the fuel and vacuum lines go. Is there a diagram of the layout of said hoses available online or possibly anyone on the south side of Brisbane with a TRX that I could take a look at to copy the layout. Any help would be greatly appreciated. Cheers AL

Pretty sure this came up very recently on the forum.

Could try search or look through active topics?

Online manual (see forum downloads) may well show the hose connections.

Quite. Few of us about here in Brisbane,AL, north and south ...I am in Boronia Heights.

Hey Al'. I had a familiar story with my motor. When the bottom ends give up, it seems they usually do so at high rpm (due to lack of oil as the TRX is accepted as often using a fair bit) so severe damage often does happen within the first few seconds of the knock becoming apparent. With the wind and loud exhausts, it might take a few seconds to figure out "Oh, What the F... was that?".

Keep caution optimism with your replacement motor. I bought a reasonably good runner, but whipped off the sump for a check anyway. Yep. Sparkles. Bottom end was so-so, piston pins quite scored. Basically, all TRX motors are at the age now where they're due for a refresh, and carry a higher risk of failure when wrung hard. As you have already found, replacement parts are getting scarce so it might be worth evaluating the risk of having to find another one in 12 mths time or so.

Re the hoses: Here's a recent post that may help... http://www.trx850.com/phpBB_forum/viewt ... ses#p99350

Thanks for the replies. I have managed to work out all bar one hose. It is the hose that when looking from the top of the carbies is the one further most forward of the two tee pieces linking the two carbs. Regards. Frustrated as fvck. Cheers AL

ITS ALIIIIIIIIIIVE. Will post some pics during the week, Whatever that last hose is for, it cant be important, its still sitting on the shed floor. Cheers and thanks for the help.

Breather from the tank???

Got that one. the one unknown is the front one of the two between the carbs.

The carburetter coolant pipe?

ALBINQLD wrote:Got that one. the one unknown is the front one of the two between the carbs.

Only fuel & overflow come from there, it's probably overflow.

Overflow sounds like it. The engine ran fine without it connected. There is one more question I have at the moment, Flat slide carbies. Both my 95 and the 98 I bought for the engine. have what seem to be flat slide carbs, what is the difference between the standard Mikuni flat slide ones on both these engines and the ones advertised on Ebay that I have seen listed for upwards of $1600.

ALBINQLD wrote:Overflow sounds like it. The engine ran fine without it connected. There is one more question I have at the moment, Flat slide carbies. Both my 95 and the 98 I bought for the engine. have what seem to be flat slide carbs, what is the difference between the standard Mikuni flat slide ones on both these engines and the ones advertised on Ebay that I have seen listed for upwards of $1600.

The name you will need is Keihin FCR 41s...if that is on the right side of the carb bundle, you are in luck, they are the racing ones ..you say that the 95 and 98 bikes you have , have these?? and the 98 model machine, you paid 450 dollars..?
Best check that first.
The standard Mikuni s are good but the Keihins are better...maybe not the 1600 dollars better,..but if you have a set for sale second hand priced...you would be the most popular at school.

Cheers and thanks all for the help in sorting out my engine change issues, I really do appreciate the help. I am new to this forum stuff, and intend to keep with it. I would like to post pictures of my TRX but not sure how to stick them on the page, (not real bright , but I can lift heavy things) I saw a post yesterday from someone asking about peoples other rides, My present on road cycle is an 88 FJ1200. Had a commodore ute I wasn't using enough to keep on the road, so swapped it on gumtree for the FJ, Back on two wheels after about 10 years without one on the road. I have several other bikes in different states of disrepair that I hope to rejuvenate as time and money permits, a couple of which are 76 RD 400, Honda 500/4, Rg250, It465, YZ 80J, TT250,TT600 plus a few more. so if someone could reply and let me know how to attach some pictures, I will. I have 2 sets of cans for the 850 now and I need to know which would be best for it, Will post pics of both at the same time so someone can let me know which is the better of the 2. Cheers AL

How do I send messages that are sitting in my outbox, (replies to private messages) I'm technically challenged when it comes to computers. Great Fitter and Turner but SUCK at computers.