Bike won't go over 40mph

Ok... i have a problem.

I have just put the bike all back together and it will not allow me to go over 40Mph??

Work carried out:

1. New Alarm
2. New fuel Filter
3. New Air Filter
4. New Exhaust
5. Oil Change
6. New Tyres, Pads and Discs
7. New Paint Job.

After all this work, and finally put back together, it will not allow me to go over 40Mph??

have you checked the carbs and sorted the fueling for the new pipes? as not doing anything to the engine/fueling/carbs could really effect the engine running

Have split the topic, problem might just not be your alarm.

No pipes kinked, connectors come loose?

What is happening when you get to 40?

Yeah, what are the symptoms?

When you get to 40 does it cough and splutter or does it just seem to top out?
Is it the same in all the gears? I'm just wondering if it comes in about the same point in the rev range in each gear?

check your plug leads as well

Kinked vacuum pipe???????????????

Throttle cables set wrong or pinched ???

Does the bike rev through the whole range when at rest and in neutral and the throttle is blipped ???

I've seen the pictures of the dismantled Cat sitting in the corner of the garage looking all sorry for itself.

I reckon it's just pissed at ya for all that abuse.

SteveCat wrote:Have split the topic, problem might just not be your alarm.

No pipes kinked, connectors come loose?

What is happening when you get to 40?

Thanks Steve for splitting the topic

I will have another look tonight at the pipe (air pies and vacuum pipe) to see if there are any kinks etc,but i have checked the front end with all air connections seem to be all fine.

The bike goes through the gears fine but seems to top out at 40Mph, it feels almost restricted to give it a better discription.

0ldcat wrote:Throttle cables set wrong or pinched ???

Does the bike rev through the whole range when at rest and in neutral and the throttle is blipped ???

When in neutral it is rev's fine, and when in low gears it also fine. But when you go up to 3rd it feels restricted and won't go above 40Mph even when climbing the gears, and it stays around 3000 RPM.

Dai-San wrote:I've seen the pictures of the dismantled Cat sitting in the corner of the garage looking all sorry for itself.

I reckon it's just pissed at ya for all that abuse.

Probably lol

Fuel tank breather kinked? not letting air in the tank?

New fuel filter on the wrong way round? the arrow should be pointing to the carbs?

Is it one of those little plastic ones? can't remember

Yes it is one of the plastic ones....

http://www.ebay.co.uk/itm/FUEL-FILTER-YAMAHA-YZF600R-THUNDER-CAT-YZF-600-/190551992325?pt=UK_Motorcycle_Parts&hash=item2c5dc8a805#ht_1700wt_1180

I will check that i have put it on correctly, also i will check that the air hose.

Thanks for your suggestions people.

clark607 wrote:

0ldcat wrote:Throttle cables set wrong or pinched ???

Does the bike rev through the whole range when at rest and in neutral and the throttle is blipped ???

When in neutral it is rev's fine, and when in low gears it also fine. But when you go up to 3rd it feels restricted and won't go above 40Mph even when climbing the gears, and it stays around 3000 RPM.

You say 3000rpm . . .

Does she rev FREELY in neutral RIGHT up the rev range to the red line ?

Also you say she's fine in the lower gears . . . you should beat 40mph in 2nd and deffo 3rd if you give it some beans

have you tried giving it the old duke of boots ? (some welly)

Yeah i have tried to give it some welly lol but it seems to get up to 40Mph in 2nd 3rd fine.

The bike rev's freely in neutral right up the rev range fine.

I just been out and checked the fuel filter, i have put that on fine. I also checked the air hose from the fuel tank and that also is connected and free from any kinks.

hmmm i wonder if all the cylinders are firing correctly??
Does it sound "right" when you rev it??
Plug leads all tight and in the correct order?

I think i would now start to back peddle, like put the original exhaust back on and see if that makes any differance.

Then try the air filter..
did you oil the new airfilter? if so have you over oiled it

Did you have the HT leads off by any chance?
Right gotta go to work Davie

furball wrote:I think i would now start to back peddle, like put the original exhaust back on and see if that makes any differance.

Then try the air filter..
did you oil the new airfilter? if so have you over oiled it

Did you have the HT leads off by any chance?
Right gotta go to work Davie

Thanks for you advice, i will check everything. I did change the plugs and oil and oil, also the exghaust filter before MOT and everything was running fine.

Then i stripped it all down and changed the fuel filter and air filter and painted the fairings, and fitted the alarm. Now i have the 40Mph fault. So i feel that it could be the alarm our possibly something to do with the air system.

But i will back track and check things out.

Thanks guys for your advice, and i will let you know how i get on today.

It doesn't sound like the fuel filter, the engine not spluttering from starvation from the seems of it. Could be the air filter, worth checking.

I have resisted blaming the alarm / immobiliser, I've a passionate dislike for them and would blame them for anything that goes wrong.
Have been trying to work out how it can work OK up to a point and then 'govern' the engine. I see it does connect to the CDI, so there is some control over the ignition.
In my late teens I built a unit which essentially erratically disrupted power to the points. It allowed the engine to start and run at a low speed but any higher the bike would then 'kangaroo hop'. Am wondering if your unit isn't a more modern version.

Might be worth chatting with the units manufacturer, they may have come across this before.

SteveCat wrote:It doesn't sound like the fuel filter, the engine not spluttering from starvation from the seems of it. Could be the air filter, worth checking.

I have resisted blaming the alarm / immobiliser, I've a passionate dislike for them and would blame them for anything that goes wrong.
Have been trying to work out how it can work OK up to a point and then 'govern' the engine. I see it does connect to the CDI, so there is some control over the ignition.
In my late teens I built a unit which essentially erratically disrupted power to the points. It allowed the engine to start and run at a low speed but any higher the bike would then 'kangaroo hop'. Am wondering if your unit isn't a more modern version.

Might be worth chatting with the units manufacturer, they may have come across this before.

Thanks for your advice, i will take the tank off this afternoon and will check the air filter. I will also take it for a spin again to see if the fault still there.

Will keep this thread updated to how i get on. thanks again people.

I'm sure you have checked this but worth mentioning. You say you have sprayed the fairing, the front air intake isn't still masked is it? (underneath the headlight, mesh grill).

Dai-San wrote:I'm sure you have checked this but worth mentioning. You say you have sprayed the fairing, the front air intake isn't still masked is it? (underneath the headlight, mesh grill).

Yeah i have removed all tape and checked all the piping from the front all the way back to the tank and the breather all seem to secure and free from any debris.

I am still stumped, as i have checked everything that people have suggested and i think that i just have to bite the bullet and take it to the garage to see what's wrong. But before i do that i will let some friends take a look to see if they can find the fault.

Will let you know how i get on, and finger's crossed that it is somthing simple lol

Can you describe its symptoms in more detail? Is it instantly cutting out like its electrical or does it feel more like its sputtering from fuel or air starvation? Is it better or worse on choke? If you back off the throttle when it happens does it suddenly fire back into life on half throttle?
It's very difficult sometimes to describe what's happening in words, are there any mechanical minded peeps near to you who could test ride the bike on your behalf?

HTH Nick

robertcains wrote:Can you describe its symptoms in more detail? Is it instantly cutting out like its electrical or does it feel more like its sputtering from fuel or air starvation? Is it better or worse on choke? If you back off the throttle when it happens does it suddenly fire back into life on half throttle?
It's very difficult sometimes to describe what's happening in words, are there any mechanical minded peeps near to you who could test ride the bike on your behalf?

HTH Nick

Hi Nick, thanks for your post.

I have some friends at work that have been riding for years, and said that they can take a look at it for me.

It is difficult like you say to try and describe the problem, but it does not feel like an electrical fault as it goes up the gears fine and rev's are fine but as soon as you reach 40 Mph it feels like its restricted and does not want to go anymore. I have also noticed that the rev counter and speedo also takes along time to move when picking up any rev's and speed once the bike is under strain ( in gear).

It ticks over fine but as soon as you go over 30/40mph it sruggles. My friend has just had a quick look and spin and he is not convinced that it is firing correctly, as he has been on it before and he confirms that it sounds completley different (not the exghaust) and thinks it is misfiring.