Decompression lever on motorbike

[taslucas]

Hello, I thought it might be easier to ask this here instead of finding another forum.

My XR400 has a decompression lever. I have never used it and never felt like I needed to. A mate had an XR for years and said the same.
A cable runs from the lever on the bars to a lever on the head.
My question is: is it going to cause any problems to take the lever and cable off and leave it off?
I can't see any issues because, like I said, I never use it anyway.



>>>tappin from tassie

[nipagu7]

it won't cause any problems if you take the lever and cable off . but they can come in handy . if you flood the carby you just hold the lever in open the throttle full and kick it fast about 6 times , this purges the rich mixture from the cylinder . also if your in a situation where it is difficult to kick the bike over you can use it to get the motor in the right part of the cycle before you kick.

[taslucas]

Yeah my mate used that technique to help when flooded. It doesn't seem to make much difference to mine (it's a pain when flooded regardless lol).
As for getting the kick start in the right position, I never have any issues with too much compression. I guess the old girl is not the tightest of engine.

>>>tappin from tassie

[threedogs]

From memory it lifts the valves a tad to lower compression, but if youre not using it anyway,why take it off.
But why not just leave it in place its not a performance or weight issue,??

[NissanGQ4.2]

Ever thought that they have a decompression lever other than 2 help kick start it? I've read something about weak gears or something

Anyway the decompression system is good for priming the bike on a cold start or clearing the carb when you fall (HOT STARTING). Leave it on.

[Maxhead]

clearing the carb when you fall. Leave it on.

That would be all the time so I agree, leave it on...lol

[taslucas]

From memory it lifts the valves a tad to lower compression, but if youre not using it anyway,why take it off.
But why not just leave it in place its not a performance or weight issue,??
The lever is in a bugger of a spot. Can get in the way of the clutch and also is vulnerable when the bike falls over lol.

Ever thought that they have a decompression lever other than 2 help kick start it? I've read something about weak gears or something

Anyway the decompression system is good for priming the bike on a cold start or clearing the carb when you fall (HOT STARTING). Leave it on.
As John said, I think it drops the valves slightly so that compression can get past them.
The bike needs no help cold starting (like fourth kick after 6 months with stale fuel), infact I reckon lowering the compression when cold would hinder a cold start and as for the flooding as I said above it never seems to make any difference (having layed it over and flooded it plenty of times in the last 8 or so years lol)

That would be all the time so I agree, leave it on...lol
You can ead

>>>tappin from tassie

[mudski]

If you have never used it in the time you have owned it. Remove it if its in the way. Just remove the lever section and leave the cable and put the lever in your spares kit, if you keep one, then you have it when needed.

Sent from my GT-N7105T using Tapatalk

[threedogs]

Might be time to give the carby a birthday with new needle and seats
and maybe double check your floats levels, lol

Focus on getting the tune spot on, IMO

[taslucas]

If you have never used it in the time you have owned it. Remove it if its in the way. Just remove the lever section and leave the cable and put the lever in your spares kit, if you keep one, then you have it when needed.

Sent from my GT-N7105T using Tapatalk
She's off! Cable and all. The little lever that the cable connects to on the head has a spring on it so when the cable is removed it holds in the "off" position.

Might be time to give the carby a birthday with new needle and seats
and maybe double check your floats levels, lol

Focus on getting the tune spot on, IMO
Woah woah woah! Ease up there, it's not that much of a tidy up lol. It idles perfect runs sweet and has plenty of power so I won't touch it for now.

>>>tappin from tassie

[NissanGQ4.2]

She's off! Cable and all. The little lever that the cable connects to on the head has a spring on it so when the cable is removed it holds in the "off" position.

Can I be the first 2 laugh when the next time your out riding its a bitch 2 start?

[taslucas]

Can I be the first 2 laugh when the next time your out riding its a bitch 2 start?
My God todd, read my replies re: the starting of the bike! It has not helped me start the bike in 8 years. :-P

>>>tappin from tassie

[taslucas]

But I'll give you first laugh rights on my first crash. Deal?

>>>tappin from tassie

[the evil twin]

I have to preface the following comments with the disclaimer that I am not an afficionado of the intracacies and black arts of motorised two wheel thingies... so I could be waaay off the mark
Quads and up are my forte after a run in with a broken ankle and a cranky Huskie in my youth and the realisation that anything with two wheels is inherently unstable unless sufficient gyroscopic rigidity is present and thus will fall over at every opportunity when your pissed.

Anyway...
I was under the impression the decomp lever that cracks the exhaust valve on petty engines was so you could slowly ease the piston juuust past TDC after compression stroke, release the lever then kick the sucker IE decomp isn't held on for the kickenzeshizzenoudazesucka part of the starting

The old school farm stationary and tractor diesels I am vaguely familiar with that had decomp were slightly different.
The decomp was needed so you could get up enough rotation speed 'easier' and then it throws off for the start to happen IE they were held on and tripped by the engine.

[threedogs]

I take it its kick start only.
I'll go 2nd dibs on a laugh ,still dont see why you needed to remove the lot/
but its your bike eh

[taslucas]

Anyway...
I was under the impression the decomp lever that cracks the exhaust valve on petty engines was so you could slowly ease the piston juuust past TDC after compression stroke, release the lever then kick the sucker IE decomp isn't held on for the kickenzeshizzenoudazesucka part of the starting



Yep that's how I understand they are ment to work. But for whatever reason mine starts fine hot or cold without following that procedure.
I know three mates with xr's that don't use the lever for starting either.





>>>tappin from tassie

[NissanGQ4.2]

My God todd, read my replies re: the starting of the bike! It has not helped me start the bike in 8 years. :-P

>>>tappin from tassie

I did read that, doesn't mean its not going 2 become a bitch 2 start

[threedogs]

Bore it out to 510cc with a high comp piston and see how you go LOL

[taslucas]

Bore it out to 510cc with a high comp piston and see how you go LOL
440 kits are common and that will be on the cards one day. The intake has been die ground and a fee little clean ups before I got it.

They are a great bike

>>>tappin from tassie

[mudski]

Yeah the XR400's are good without the decomp lever. Probably the only good bike Honda ever released. I used to ride with guys on 400's. Not one used the lever.


...and if you haven't fallen off yet. You ain't riding hard enough. That was my motto, until I gave up after a few trips to the hospital. 20 years later I can't even lift my leg over the seat. Lol.

[Maxhead]

Yeah the XR400's are good Probably the only good bike Honda ever released.

You wanker Mark..............:band:

[taslucas]

Yeah the XR400's are good without the decomp lever. Probably the only good bike Honda ever released. I used to ride with guys on 400's. Not one used the lever.


...and if you haven't fallen off yet. You ain't riding hard enough. That was my motto, until I gave up after a few trips to the hospital. 20 years later I can't even lift my leg over the seat. Lol.
Well I think I've proven the going hard enough bit lol but only one trip to hospital was needed

>>>tappin from tassie

[mudski]

You wanker Mark..............:band:
Tell me another Honda that was as popular than the XR400?


Well I think I've proven the going hard enough bit lol but only one trip to hospital was needed

>>>tappin from tassie

Yeah i reckon your a better/ smarter rider than i was then. I used to be the only 2 stroker riding in a group on big bore 4 strokers so i had something to prove. Which didnt always turn out in my favour.
This talk makes me wanna go out and get a trail bike again....lol

Sent from my SM-P600 using Tapatalk

[nissannewby]

Tell me another Honda that was as popular than the XR400?



Yeah i reckon your a better/ smarter rider than i was then. I used to be the only 2 stroker riding in a group on big bore 4 strokers so i had something to prove. Which didnt always turn out in my favour.
This talk makes me wanna go out and get a trail bike again....lol

Sent from my SM-P600 using Tapatalk

Ct110.....

[Ben-e-boy]

Yeah i reckon your a better/ smarter rider than i was then. I used to be the only 2 stroker riding in a group on big bore 4 strokers so i had something to prove. Which didnt always turn out in my favour.
This talk makes me wanna go out and get a trail bike again....lol

Sent from my SM-P600 using Tapatalk

I just sold my ktm 300 exc last week. You could have bought that.

[threedogs]

The XL250 was a huge seller for honda,
I was working mainly at honda dealerships all over Aust.
These were early bikes like the 250 Elsinor Moto X bike

[mudski]

Ct110.....
Excluding what aus post bought. Lol


I just sold my ktm 300 exc last week. You could have bought that.
Sorry Ben. Im a Husky boy. Had a wr250, then wr360. I think now i could only ride a xr200 or my body would snap in half.
Got me thinking about them again though....


Sent from my SM-P600 using Tapatalk

[mudski]

The XL250 was a huge seller for honda,
I was working mainly at honda dealerships all over Aust.
These were early bikes like the 250 Elsinor Moto X bike
I reckon the xr400 out sold the mighty XL though.

Sent from my SM-P600 using Tapatalk

[taslucas]

I would love to do some touring one day Plasnart.

Yeah go the mighty xr400 in the late 90s with the Ballard boys!

>>>tappin from tassie