ty 250 mono aftermarket parts

Got a technical question? Ask it in here.

Moderator: Moderators

Ferretflasher
A grade participant
A grade participant
Posts: 102
Joined: Fri Nov 24, 2006 7:45 am
Location: grimethorpe, UK

Re: ty 250 mono aftermarket parts

Postby Ferretflasher » Wed Dec 18, 2013 12:03 am

I generally find the eBay UK has the most variety of mono parts but eBay.fr has the better quality stuff simply because they never really had the abuse we poms gave the old monos. For example I buy most of my forks from France as they are cheaper and the alloy bits.lugs are rarely broken or threads stripped.

Fit a plastic TY R tank to a TYS will be a faff, you will have to cut off the mushroom lugs and try tapping then out M6 .... but you need to check the centres are same. Back mount is a bigger rubber pad IIRC but uses same fixing location. Will prove a few hours entertainment to distract you from cricket etc



millerme
Junior participant
Junior participant
Posts: 1
Joined: Mon Feb 03, 2014 6:27 am
Bike: ty250 EVO hybrid

Re: ty 250 mono aftermarket parts

Postby millerme » Mon Feb 03, 2014 6:55 am

here in the UK I have a after market ty 250 mono rear shock
tyz 1 cv.png
tyz 1 cv.png (171.58 KiB) Viewed 38222 times



Ferretflasher
A grade participant
A grade participant
Posts: 102
Joined: Fri Nov 24, 2006 7:45 am
Location: grimethorpe, UK

Re: ty 250 mono aftermarket parts

Postby Ferretflasher » Tue Nov 10, 2015 9:04 pm

Have started on my next bike incorporating all the lessons learned from previous 4 machines. Latest improvement has be to adopt Fibre Reed Valve petals. As these old mono engines are based on a DT400 MX motor seems logical to fit petals for this motor. Huge improvement over the OEM steel items I obtain mine form in UK at Yambits , Borougbridge. Ask for the above type the part# is Hy Tech Reeds HT029.
Second improvement has bee to fit a 30 Flat side MIKUNI carb, choke needs moding as its wrong side and lift needle 1 notch otherwise its a superb fueling setup now, no pinking and very smooth. Throoootle cable needs shortening 20mm to use with modern twist grip.
Generally can mix it with modern machinery now no prob. More later as am with an original barrel with long inlet, aim to see if shortening has any descernable impact on the average clubman level of wobbling. More later.
FF



david_engel
Junior participant
Junior participant
Posts: 1
Joined: Sat Nov 28, 2015 5:58 pm
Bike: TY175 / TY250R

Re: ty 250 mono aftermarket parts

Postby david_engel » Sat Nov 28, 2015 6:07 pm

Does a TY250Z shock (assume that is what is in the previous picture given the file name) fit a TY250R and will the spring rate and damping be correct ie is the mono linkage action similar? Apparently, Ohlins list a build for a 1993 TY250z so I am thinking of getting one for my 1988 TY250R.



Melvyn
Junior participant
Junior participant
Posts: 1
Joined: Wed Mar 22, 2017 8:50 am
Bike: Yamaha TY250R Pinky
Club: Hillingdon and Uxbridge MC

Re: ty 250 mono aftermarket parts

Postby Melvyn » Sun Mar 26, 2017 11:00 pm

Ferretflasher wrote:Have started on my next bike incorporating all the lessons learned from previous 4 machines. Latest improvement has be to adopt Fibre Reed Valve petals. As these old mono engines are based on a DT400 MX motor seems logical to fit petals for this motor. Huge improvement over the OEM steel items I obtain mine form in UK at Yambits , Borougbridge. Ask for the above type the part# is Hy Tech Reeds HT029.
Second improvement has bee to fit a 30 Flat side MIKUNI carb, choke needs moding as its wrong side and lift needle 1 notch otherwise its a superb fueling setup now, no pinking and very smooth. Throoootle cable needs shortening 20mm to use with modern twist grip.
Generally can mix it with modern machinery now no prob. More later as am with an original barrel with long inlet, aim to see if shortening has any descernable impact on the average clubman level of wobbling. More later.
FF


Hi FF and any other readers!

I've just joined this forum so any advice both on using it and my bike problems would be appreciated!
My bike is a '92 TY250 Pinky which has lead a reasonably sheltered life spending most of its life following trials around the Hull, UK area before I brought it down to London in 2006.Then being a complete novice at trials I gradually tidied up the bike with the help of John Cane @ TY Trail & Trials mainly.

The bike is on its first rebore with the correct no.OEM piston / new small end, mains and seals (pressure tested at low PSI for 10 mins) / ultrasonically cleaned & refurbished original Tekei carb with relevant new parts (slide & bore in fair condition)/ Hy-Tech fibre reeds fitted / OEM air filter & free flow late air box / timing checked as spot on / de-coked exhaust with front box split cleaned re-packed and welded back, and a WES soft rear silencer fitted / 50:1 semi synthetic fuel mixed used (considering trying full synthetic @ 70 or 80:1...

The bike still tends to be a bit rattly (as I'm led to understand they all do) - but my two problems are knocking/pinking (only on the overrun) and the engine failing to drop its revs when I shut the throttle - giving little engine braking (indicating a lean mixture / air getting in despite all above checks?)... both these issues may be exaggerated when the engine gets hot. In desperation I have tried a colder plug by up to two steps to little effect... and whatever Keyster main / pilot jets I could get to enrichen the mixture also trying different needle heights (although naturally its the first 1/4 to 1/2 throttle opening which is problematic as higher revs are fine...)

Again, all of the above to no avail - indeed at the moment to keep things manageable, the air screw is all the way in (not 1 1/2 out) and ticker is purely on the throttle slide stop... throttle cable is adjusted with the recommended initial slack and it moves well...

What I did notice on the last stripping down is that the Hy-Tech fire reeds do not sit on the reed cage rubber facing as one might expect but are around up to 1mm off (on a bike this age the facing rubber must be quite hard, no?) - Is this significant would one think?

I am so frustrated that I am considering fitting a 28mm D slide Keihin carb - any thoughts here?
Also do Moto Tassarini do a V Force reed cage assembly which would fit this bike?

Thanks for any feedback on this!

All the best

Melvyn



Ferretflasher
A grade participant
A grade participant
Posts: 102
Joined: Fri Nov 24, 2006 7:45 am
Location: grimethorpe, UK

Re: ty 250 mono aftermarket parts

Postby Ferretflasher » Wed May 31, 2017 9:44 pm

Hi Melvyn,
After numerous tests, I arrived at the conclusion that the standard TK carb is rubbish!
Cut your losses and fit a Mikuni or OKO flat slider, you will not be disappointed. I have the Mikuni fitted now, Ihad to change the choke lever over to otherside and the needle needs lifting 1 or 2 notches as its lean on the top end.
It starts first or second kick, does not leak and run superb on bottom end and pick up.
Abandon that TK , it was crap to start with and soon get s made-up inside, no amount of ultra sonic faffing will clean it out!!

Reeds should sit flat on rubber substrate with virtually no gap. Don't get rid of big steel stopper. Check rubber, if its worn [from dust dirt grit] its gone! Get another from eBay rubber must be in good condition.

Use regular un leaded fuel 50:1 synthetic premix and tune carb by looking at spark plug. YOU CANNOT 100% eliminate Pinking but with a good Mikuni carb you can reduce by 95%.
FF




Return to “Technical help”

Who is online

Users browsing this forum: No registered users and 1 guest