TU 250 Volty trouble

[RuffStuff]

Hi ive got a tu 250 volty, its a 1995 jap import ( apparently the same as 97 uk model) and im currently hacking about on it in freezing temps
Im having a few issues, from what i can find out its the same ish motor as the gn and gz, 250 single, 4 valve and pretty basic, as of any other info i cant find much, a few parts diagrams and thats about it, so if anyones got any stuff they want to post up id be very grateful :roll:

OK so on to the problems, is it just me or is 5th useless to everyone ?
itll do 50 in 3rd 4th and 5th but anything over that in 5th seems to be an issue, i can ring it to death in 4th and see 120 kph on the clocks on the odd occasion but 110 is the norm and i feel really mean on it cos im 300lbs :tongue:

if i shift up into 5th at say just over 60mph ( most days it does it no matter what speed i shift to 5th) it seems to start fueling really bad and jumping about and then rolls down to 55 or less and just doesnt respond, even to wide open, almost like its trying to stall and it needs a downshift to avoid a wipeout on the bypass i have to go down

even 4th is causing some issues and has also been doing this occasionally, im also finding it doesnt like to sit on part throttle in 4th or 5th for the 50 mph coast road to my girlfriends and seems to surge and sometimes itll need a down shift to 3rd just to keep with the traffic flow

Im very mechanically minded, have built and raced bikes since i was a kid but this has got me beaten :cry:
I also think the massive lack of info for this model isnt helping me either so if anyones got an idea what it is or has a manual in pdf let me know

Ive emptied the tank n filled with fresh, run redex thru the carb, stripped and cleaned the bottom half out, blown the jets thru, set the mix screw, its got a new plug, the filters clean, ive changed the oil and put a brand new battery on it

ill need new carb top screws before i can get into the top as they have seized solid and need driling out, all i know is its a mikuni ( see link for diagram )
http://www.cmsnl.com/suzuki-tu250-1997- ... FIG10.html (http://www.cmsnl.com/suzuki-tu250-1997-xv_model14201/partslist/FIG10.html)

i wondered if it was the needle, but im not too sure, the symptoms are too erratic and only in the top 2 cogs, no one round here has one or even something similar so i dont know if this is just something they do or not

any help will be greatly appreciated :2tup:
Gaz

[blaine]

Try riding with choke partly on.If runs better,needs needle adjustment and larger main jet.Possibly a "130.Good luck.

[Sarris]

I go 6'-1" and about 280 lbs and I really recommend the 16 tooth front sprocket. With it I can maintain 60-65 mph without a problem, although my GeeZer really likes 55 mph best. However, the 16 tooth front sprocket makes 5th gear virtually a cruise gear only without much acceleration capability.

Service manual for the GZ is here on site.

See Ron Ayers for parts microfiche here: Ron Ayers (http://fiche.ronayers.com/)

Good Luck

:rawk:

[RuffStuff]

i did try riding with the choke on but the vibes just rock it shut when its warmed up, its a pull on one next to the petrol tap, as said its fine in the first 3 gears and normally the 4th

i did wonder about the 16 tooth fr cog, so i take it thats going up one and just riding it as a 4 speed then ?
how much difference does that make to the around town nippyness of the bike ?
ive found a place selling 2 down rr cogs pretty cheap, maybe that would be a good comprimise

Im going to have to try and get on another pc to see the manual (wont load up for some reason) but can anyone tell just what the differences are between the tu and gz engines ?
I know the carbs are a different set up and not much else

[Easy Rider]

However, the 16 tooth front sprocket makes 5th gear virtually a cruise gear only without much acceleration capability.

Time out. I thought that was his COMPLAINT. Did I miss something ??
Upping the final drive ratio would make the problem worse, not better.
Maybe his drive ratio is different than the stock GZ already.

I suspect that wind resistance plus 300 lbs. has something to do with it.......but it still doesn't sound quite right.

[RuffStuff]

i did consider making 5th totally redundant by changing the sprockets as im so fed up of it doing what it does, it does it even on the calmest of days if its windy ill just see 60 tops and no more ringing it out in 4th

I have no other option but fast roads out of town, 1 way in, 1 way out :-(

is it possible that the motor just cannot do a high revs shift into 5th ?
ive never known any other bike to do it tho

I know being big means ill never get it close to 80 but all i want is to be able to hook into 5th and it sit at 70 or i risk getting wiped out on the bypass, which has nearly happened when my old scooter seized and turned the lights off at 3am and the following car was doing 110 behind me

[alantf]

can anyone tell just what the differences are between the tu and gz engines ?
I know the carbs are a different set up

Yes, totally different - in fact so different that the tu doesn't have one .... it's fuel injected. :) I think that fuel injection would make a world of difference to the gz :2tup:

[RuffStuff]

its the old one, not the new model
same frame as the gn, supposed to be same motor, 18 fr n 17 rr wheels

although wouldnt mind the new one, could get some decent rubber on it then

heres the only pic ive got of it with my balding mate sat on it

http://www.southportriders.com/Images/brett_250.jpg

[patrick_777]

With a name like Volty, you should just paint it rainbow and hang tassles off the barends.

[Easy Rider]

I know being big means ill never get it close to 80 but all i want is to be able to hook into 5th and it sit at 70 or i risk getting wiped out on the bypass,

If you have no windshield, when the bike is going 70, you are fighting a 70 MPH headwind......automatically.......against the bike AND your..mmm....sizeable body,which acts like a sail.

I think the general consensus here is that 70 is about the average top speed, and that under ideal conditions. Most are only "comfortable" up to about 65.

My opinion is that you are hoping for more than you will ever get..........but your "using only 4 gears" idea is interesting. The real solution is to trade it in for a bike with about twice as many CCs; several here have done that.

Cheers. Good luck.

[patrick_777]

The real solution is to trade it in for a bike with about twice as many CCs; several OF US here have done that.

Fixed it for ya... :2tup:

Some of us still have our GZs though.

[alantf]

TRADITIONAL fish & chips? Whenever I go back to England, for my holidays, I've never EVER found any that resemble in any way, shape, or form, the fish & chips I remember from my childhood (in the 1950s) :cry:

Chips cooked in lard, not oil, & large pieces of North Sea, flakey, cod in crisp batter. Ah for the simple joys of a forgotten era! :poorbaby:

[Easy Rider]

[quote="Easy Rider":1i1pbuyc]The real solution is to trade it in for a bike with about twice as many CCs; several OF US here have done that.

Fixed it for ya... :2tup:
[/quote:1i1pbuyc]

WTF. You are going to be the grammar police here too ???

:redflip: :hide:

[patrick_777]

Just emphasizing what you didn't... :redflip:

[dannylightning]

well i will tell you, after i did a few mods too my bike it ran like complete crap had to put in a new jet and change out the needles and all that good stuff. the first few rpm's of each gear it had plenty of power but as the rpm's got higher no torque at all, the engine would just rev up and and the bike was not going. this was after changing my pipes and putting in a k&N air filter. so i took the filter out and rode around like that till i got my jet kit. than it started to get really cold at night here. the bike was running really bad when it was cold.

got my jet kit and installed it, put my k&n filter back in and have never had a problem since. so if the bike was modified at all it just might need a bigger jet but being a big guy on a 250 probably wont help either.

[RuffStuff]

its totally standard, 8k on the clock, sat in 3 sheds for last 10 years if not longer, got about 3 scratches on it all for the princely sum of £250

I know im not going to have a rocket ship but its defo got a problem happening with 5th gear and the fueling while its up there, im not expecting it to be quick, just to be right n be as quick as it can be for the odd fast road im forced to go on, normal speed the rest of the way is 30 to 50

it was originally got as a winter hack but then the cbr shat its kecks on me so its been pressed into action early and tell you wot i forgot how much fun little bikes are, ive been hacking down gravel strewn wet roads scraping my pegs in 0 degree temps, if id tried that on my cbr id of been in a hedge or need new pants

If i can sort the problem out, maybe someones had a similar thing with there bike then ill be happy knowing im not going to burn the valves out or that something that needs fixing wont break on me

then i was thinking some hand guards, maybe heated grips but unsure if the gen can handle them, a little screen and maybe a rack for it n dual purpose hoops, n i could see myself using it no problem for a good few years, for what its cost me i dont need to sell it

[RuffStuff]

With a name like Volty, you should just paint it rainbow and hang tassles off the barends.
were not in america here :neener:

it is the gayest name for a bike ive ever come across tho

[RuffStuff]

ok ive been out on it again tonight and its still doing it, it wont even get to 60 in 5th from an early roll on, ive tried alsorts on it tonight to narrow down the problem but its pulling 110k in 4th no problem

has no one got any ideas for me ???

[Water Warrior 2]

Have you done a valve adjust and compression test ? The bike is 15 years old, maybe it is just getting tired.

[RuffStuff]

its all good and very low miles 8k, plus its just in the one gear, hence why im being baffled by it

[blaine]

My guess would be to drop down one tooth on front sprocket.If working fine in lower gears,need more revs for 5th gear.

[RuffStuff]

hmm thats got me wondering if its already had a tooth up on the front you know, it does seem strange that it cant pull 5th at all, ill check that in the morning, but then from what ive read on here it should be able to hold the speed when its shifted up hmmmm

[blaine]

That's my thinking,that somebody went one up on sprocket.

[Water Warrior 2]

its all good and very low miles 8k, plus its just in the one gear, hence why im being baffled by it
My bad, just went back to the beginning. Okay here is another idea that might be the problem. New plug or not, you have a weak ignition system that is only showing up when the engine is at it's highest load(5th gear). I have seen this on cages so it could happen on a bike. You may want to check all the ignition system wires for frays or damage.

[RuffStuff]

yeah ive already done the whole loom, as there was a fault thought to be in the switchgear but turned out to be a duff connector behind the battery, the rest of the loom is perfect all the way thru

im thinking its the cog, maybe the jap one has a smaller front than uk spec so its gone up one by someone buying a replacement kit

[RuffStuff]

right ive had the cover off now and its got a 15 fr cog on, i cant find any specs of the early jap spec one anywhere so not to sure if its right or not

im at a loss with this now, im being beaten by a 250 grrrr

time for ebay me thinks

[Easy Rider]

im at a loss with this now, im being beaten by a 250 grrrr

Time to review the basics:

Several of us have said that the GZ is an under-powered bike that won't pull 70 reliably in any but the most ideal conditions. Having a 300 LB rider and no windshield only makes matters worse.

There is no reason to think that your similar bike would be any different.

I (several of us ?) think what you are describing is VERY likely normal.......and so far, you haven't said anything that would tend to indicate that it is NOT normal.

Before you spend a lot time, effort and maybe money on this "problem" you need an onsite test ride by someone who is experienced in small bikes like that. Seriously.

[bonehead]

Hell, I'm happy when I can get 60mph.

[RuffStuff]

yh im happy with it, but from everything i can work out and the little bikes ive had before they have all been able to hold the speed in 5th and atleast accelerate a little bit, this just rolls off 15 mph as soon as its shifted

my options are give it absolute death up the bypass in 4th or risk getting rear ended, either raise or lower the gearing, fors and againsts for each option or lob it on ebay and make a profit on it

everyone drives faster round here and most on there phones and so it would seem none of them are arsed about watching for bikes, ive got the scars to prove it

[bonehead]

The 2 250's I had back in the 70's would haul my ass around at hiway speeds no problem, then I bought this one and could'nt figure out why I can't get over 60. Then it hit me, the other 100 lbs I'm carrying around. DUH!!!

[RuffStuff]

hahaha ive been this big before n had 250s n been skinny as hell n still theyd only do 80 at a max, bar the rgvs
i just want it to sit n cruise at say 65 without it blowing itself to bits

[alantf]

From what I can gather, there are two versions of the gz250 - the American & the European - I think that the emissions regs in America make their version even slower than ours. When I say "ours", I'm assuming that the English/European versions are the same. I can join the autopista (motorway) at 60 km/hr (just under 40 mph) in 5th, & accelerate to 100km/hr(62mph) with no problems. (although it's REALLY happy at 90 km/hr) I'm 12½ stones (185 lbs) & don't have a windshield. Going on all this, I don't know what the answer is, but I DO think that you have a problem. :jo:

[trykemike]

hello

TRY A BIGGER MAIN JET 125 PERHAPS. iT WORKED FOR ME . i'M 5'6" 165 LBS i CAN TOP 80 MPH MOST DAYS IF NEEDED.

[RuffStuff]

right as strange as it is its now pulling higher speed in top, aslong as i shift in early, i shifted up a few times tonight at under 60 n kept it wide open n slowly it lost 5 or so mph as usual and then would slowly chugg thru what feels like the motor really strugling to breathe and then got upto just over 60 almost 65 sat half up and after a few trys and some serious tucking in, which is hard at my size lol i saw just over 110 kph on the jap clocks
although after a mile like this is starts to stop fueling, its really weird
i did try a few shift up at high revs tho and it still did the same jerking n lack of fueling and it still goes quicker in 4th

it seems happy around town at 40kph, sits there nice, likes to be just under 100k on the clocks on the open road but just not in top

i think maybe this bikes just got some sort of self harming issue i dont know about, its defo a bit emo

[burkbuilds]

Reading your last post reminded me of how my GZ ran when I took a couple of two hour highway trips on it. I remember that I was having trouble trying to even get to 65 mph for the first 30 minutes or so, then I started noticing that I could hit 70 and occasionally 75 mph briefly as the bike got warm, well probably hot for that matter. Maintaining those speeds on a GZ is practically impossible though, but I've actually hit 82 mph once going downhill with a tailwind for about 5 seconds. I am about 80 lbs lighter than you are and my guess would be that you are going to have difficulty getting to 65 and maintaining it will be even tougher no matter how well the bike is running. That was the only reason I finally sold my GZ and bought a Vulcan 500. Like you, I needed to be able to run with the pack in fast moving highway traffic to keep from getting run over. If that's as important to you as it turned out to be to me, then you probably need to consider buying a bike with more displacement. The 250 only puts out somewhere around 20-22 horsepower, my Vulcan 500 is only about 30% heavier than the 250 but it puts out twice that amount in horsepower and it makes a difference when you need to go faster.

[RuffStuff]

yeah ive got a currently in bits cbr 600, this was pressed into action early as it was originally going to be next yrs winter hack

its not fast but its good fun dragging the pegs everywhere, just a shame theres only the fast roads to get out of the village i live in, its sound round town n even handles the back roads well enough to have some fun, itll sit at 70 in 4th all day but it sounds like its going to throw its rod lol

im thinking fix the cbr n flog it n maybe flog this too as theyre fetching good cash atm and then get an old yzf 750 cos theres not much better comfier way to hit 170 daily :D

[blaine]

Did you try running wide open,shutting down,and checking plug for lean mixture.If plug is white,need larger main jet.

[RuffStuff]

yeah i didnt tonight, it was 2 am and pitch black and only just above freezing, tbh i think the only thing i havent done is a plug chop, but the old plug looked nice n right when i swopped it out a few weeks back

[RuffStuff]

its still doing it, ive kind of got a way around it figured out, but ive actually been trying to ride it how its meant to be ridden and i tell u what, i love it, proper good little bike
dragging the pegs in the ice, bouncing off potholes etc, copes with it all, around town speeds its a little rocket and i really dont want to sell it now lol
see why you guys built a forum for these things :D

[Water Warrior 2]

You have been assimulated. It really is a magic little bike when ridden within it's abilities and design.

[RuffStuff]

yeah i thought today id play in the traffic as i was in no rush and it shined, ive seen glimpses but obviously been trying to sort this fueling issue out
im made up, just a shame i have to use some fast roads around mine, if i end up working local or living at my girlfriends in town itll be laughing and im toying with an sv again for bigger duties

[alantf]

Whereabouts are you, near Liverpool? Just idle curiosity, but I've got my English road atlas on the bookshelf. :)

[RuffStuff]

Formbingtonshire upon the sea, its shit, bypass in bypass out and a fast back road across the moss, not little bikes friendly til you get off those roads

[alantf]

Formbingtonshire upon the sea, its shit, bypass in bypass out and a fast back road across the moss, not little bikes friendly til you get off those roads

I can only assume you're joking. No such place in my road atlas, & google's telling me to p**s off! :??:

[RuffStuff]

formby, its shit so we gave it a gay name hahaha
as said 3 fast roads out, the back roads even faster than the bypass, spot on, on a 600 for some good fast fun, not so friendly to a little 250

[alantf]

formby

O.k., so no jokes about leaning on a lamp post, eh George! :lol:

[music man]

The 2 250's I had back in the 70's would haul my ass around at hiway speeds no problem, then I bought this one and could'nt figure out why I can't get over 60. Then it hit me, the other 100 lbs I'm carrying around. DUH!!!


Also back in the 70's they didn't have the emission standards for motorcycles they have now, so the motorcycle manufacturers could squeeze more out of the little 250 engines.


P.S. the extra 100 pounds probably wouldn't have anything to do with it :whistle:

[Easy Rider]

The 2 250's I had back in the 70's would haul my ass around at hiway speeds no problem,


Also back in the 70's they didn't have the emission standards for motorcycles they have now, so the motorcycle manufacturers could squeeze more out of the little 250 engines.

ALSO back in the 70's, quite a few 250 bikes were 2-cycle....which makes up to 2X the HP of a 4 stroke. :cool:

[RuffStuff]

yh ive had a good few 2t 250s and a few 4ts ones aswell, been heavier and still got 80 out of the 4ts
this is still weird, some days itll do 70 fine, then others it cant do 60 and if i draft a car i can get nearly 80 out of it.
im putting it down to being an old style really basic engine tbh now, fuelings as good as its going to get

[music man]

ALSO back in the 70's, quite a few 250 bikes were 2-cycle....which makes up to 2X the HP of a 4 stroke. :cool:


Very true Easy :2tup: