Yamaha TRX850 Enthusiasts Forum

Hi guys and gals

I'm fitting a pair of FCRs on my bike and wanted to check what to do with all the hoses that are on the original Mikunis. Apologies in advance for the daft questions, I am no mechanic expert but generally keen to undo and redo/rebuild things.

So between the FCRs, I have the fuel intake (at the bottom - towards the battery) & fuel overflow (at the top - towards the steering column) > think I'm good so far

Now what do i do with the following:

- The 2 drain hoses?
- The 2 hoses that link the Mikunis with the cooling system?

Am I missing anything else other than the above?

Also, the rubber connectors I have are fairly thus tight meaning they are a real pain to fit the carbs back onto the engine... do you guys have any tips?

Thanks
Adrien

Ok, it`s simple really.The FCR`s need a fuel supply from the Vacuum fuel pump and that`s it!
Those small bore coolant hoses can simply be joined to create a loop or you can plug them altogether (small stainless bolt and a cable tie), they were there to help stop carb icing on the stock carbs.
I`m not near my bike and cannot remember if the FCR`s have float bowl drains.
I don`t think they do so if they haven`t you don`t need to worry about those either.
Basically if you`ve got a fuel supply all those other hoses can be taken off or plugged.Those hoses that go to the frame can be taken off, the CV carbs 12mm or so bore open to atmosphere hoses that went towards the top of the carbs on the downturned spigots, the ones with the plastic flash/flame arrestors in, can be junked too.
That cam cover breather hose could be routed to the back of the bike or as I`ve done you can fit a push fit filter, they`re readily available K & N do them, my breather nestles between my Ramair pod filters held in place with a cable tie.
I`ve utilised a different type of push fit filter with some open cell sponge filling, it`s designed for aquaria but works just the same and is VERY cheap when compared to the K & N items.
FCR`s are so much better all round, and you`ll love the power increase they`ll give you.
Carb rubbers can be placed in near boiling water to soften them, then a light smear of silicon grease or vaseline will aid in fitting them.

Thanks for all the info and tips Mince! Can' wait to give it a go tomorrow!

After a bit of a fight, FCRs are finally on!! The throttle return isn't as sharp/quick as with the Mikuni's and was wondering if this was normal?

Still need to sort out the hoses I don't need and secure the fuel hoses etc but couldn't resist firing the bike up... very interesting sound coming from the carbs!

drix wrote:After a bit of a fight, FCRs are finally on!! The throttle return isn't as sharp/quick as with the Mikuni's and was wondering if this was normal?

Still need to sort out the hoses I don't need and secure the fuel hoses etc but couldn't resist firing the bike up... very interesting sound coming from the carbs!

Have you fitted push / pull cables?

phuk72 wrote:

drix wrote:After a bit of a fight, FCRs are finally on!! The throttle return isn't as sharp/quick as with the Mikuni's and was wondering if this was normal?

Still need to sort out the hoses I don't need and secure the fuel hoses etc but couldn't resist firing the bike up... very interesting sound coming from the carbs!

Have you fitted push / pull cables?

Both cables are installed. The return was fine before fitting the FCRs on the bike, cables are going through the obvious passage on the bike so not sure what I else I could do.

drix wrote:

phuk72 wrote:

drix wrote:After a bit of a fight, FCRs are finally on!! The throttle return isn't as sharp/quick as with the Mikuni's and was wondering if this was normal?

Still need to sort out the hoses I don't need and secure the fuel hoses etc but couldn't resist firing the bike up... very interesting sound coming from the carbs!

Have you fitted push / pull cables?

Both cables are installed. The return was fine before fitting the FCRs on the bike, cables are going through the obvious passage on the bike so not sure what I else I could do.

Mine slams shut when hands off throttle so you must have a to tight bend somewhere or so...take cables off and turn the drum by hand a let it go...should SLAM shut....

Killerwhale wrote:Mine slams shut when hands off throttle so you must have a to tight bend somewhere or so...take cables off and turn the drum by hand a let it go...should SLAM shut....

Yep, it should close quickly. Have you overtightened both cables slightly? Even a small over-adjustment can cause problems.

OK, I'll play around with the cables over the week end. So close yet so far!

or..................it's drawing air from somewhere and running lean............

Have you bought the TRX 'specific' kit? as in full kit with new cables, adapters & filters, etc? or are you adapting a set to fit?

I only ask because this offers the option of using standard airbox with adaptors or using the filters as supplied so Mr Warhol could have a point & depends on whether you have a good seal between carbs & filters, etc. Is the slow throttle return poor when the engine is switched off? (if so will just be a routing or binding problem) Which throttle cables have you used? The kit version will come with new push-pull cables. Sometimes slight over tightening even at the throttle end clamp can cause restriction to movement.

Are you attempting to set these up with no dyno time at all? It'll cost you more than you'll save in the long run if you don't?

dandywarhol wrote:or..................it's drawing air from somewhere and running lean............

Oh, i took it for granted it was the physical throttle and not an idle hunt. We´ll i´m speaking Swenglish so...

Killerwhale wrote:

dandywarhol wrote:or..................it's drawing air from somewhere and running lean............

Oh, i took it for granted it was the physical throttle and not an idle hunt. We´ll i´m speaking Swenglish so...

That's how I read it too

I'm thinking outside the box........................

I'm talking about the physical throttle's return when engine off.

These FCRs came from a bank of 4 that got split. They came with KN filters (which are poorly adapted to fit so will get new ones) cables and throttle (not sure of their origin/what they were supposed to be used on).The guy I got them from made the mods and was running them on his TRX, standard engine with a set of cans which is the same config I have. Don't think dyno time would be required although the bike is in need of a good service for the next season so might have that done properly.

I'll play with the cable setting, see if they are too tight or not, finish off the install properly and test Dandy's suggestion.