loss of speed

[hart16]

Hi , cananyone give me a a solution

my son has a honda x8r 50cc , which has been derestricted and was capable of 50 + mph , it now only reaches 35 mph .

Any explanations would be appreciated

Malc

[Timmeh]

I'd check the sparkplug, the air filter, and then the compression in that order.


____________________
GSXR400 x2 | '94 RVF400 | '93 TZR125 4DL (again)
20:22:30 BLUEX5: i would love to be forced to undergo a**l plugging with different sizes
20:48:18 Temeluchus: comp you hunk of smouldering homos3x you

[hart16]

Thanks for that , can do spark plug and filter . Can you explain re the compression ?

[Timmeh]

Basically you're testing how good the rings are sealing in the bore.

It screws into where the sparkplug goes, you turn the engine over and it gives you a reading.

You should check the value you get using a haynes manual or similar, if its down on compression then it will need a top-end rebuild.
____________________
GSXR400 x2 | '94 RVF400 | '93 TZR125 4DL (again)
20:22:30 BLUEX5: i would love to be forced to undergo a**l plugging with different sizes
20:48:18 Temeluchus: comp you hunk of smouldering homos3x you

[Alexio]

If you take the bike to any garage they'll be able to do a compression test on any bike that size in a matter of minutes, unless you happen to have a pressure gauge laying around with the right attachment for this purpose.

If they're nice they probably won't even charge for it but let you make up your mind as to your options depending on what the compression test reveals.

[hmmmnz]

i think its time for a decoke,
mixing oil and fuel together makes for a very dirty exhaust,
obviously (or maybe not) a 2 stroke relys on exhaust to get alot of its power (a return pulse stops fuel just passing straight through the cylinder) when the exhaust gets carboned up, the frequency of the pulse changes and stops being as effective.
so you end up losing alot of power,

decoking...
there are a couple of ways of doing this,

1. fire...
cut the exhaust open, get the gas (blow torch) and burn the carbon out.

2. chemically...
get some caustic soda mix with water, but a bung in one end of your exhaust and pour the mixture down the other,
leave for a few hours, or overnight, then drain it out and refit and go for a blast....


like any good 2 stroke, the lovely carbon builds up every where,
so every few thousand miles, you have to pull off the head and scrape all the carbon offf the top of the piston and down the exhaust port, make sure the rings are free and still can compress and expand,



these are easy jobs and requires only the very basic tools
do those things ive said, and do them on a regular basis and your wee smokey 2 stroke will better for it,




caution..... caustic soda is caustic!!! wear gloves and dont let it get on the skin
____________________
the humans are dead
I kick arse for the lord
Wiring Diagrams BIDNIP it bitches

[Kickstart]

[CBA]

I was knee-deep in some engineering books a while back, I stumbled upon some ancient decarbonising methods:

1: run the engine till it is really hot, then remove the sparkplug and jet pure oxygen into the engine, turn the engine by hand every 30 seconds or so - the oxygen burns the carbon away, best done with exhaust removed.

2: run it till its hot, take off the air filter (maybe tweak mixture to get it running good), and spray clean water into the air intake .(use a kitchen spray bottle or similar - has to have a fine mist setting) .
- the water vaporises into steam and effectively steam cleans the inside of the engine, the engine doesn't get waterlogged, since the water is vaporised and goes out with the rest of the exhaust gasses. this is ok to do with exhaust on, since the steam will Clean the exhaust itself, just keep the revs high.