Okay so im havin my engine rebored next week, what do peope think is a good rebore size. At the moment i think its standard, also i need new reeds as my one broke, are the boysen pro any good? And what jets should i get to matc the new reeds and bore. Thanks
rebore opinions plus what reeds and jetting to suit
- Thread starter Rob-daisy
- Start date
You never ever want to bore or over bore more than you have to. Over boring will give you no noticeable difference in power. If the cylinder is scored good then it needs to be rough bored to see what size piston will work before they do the honing. If the cylinder is in good shape then sometimes a honing will fix it up. You never want to bore more than you have to. As for reeds boyesen makes good petals for the stock cage. If you have the funds v-force 4's are very nice. You will have to to some plug chops once it is all together to confirm jetting.
Thanks nit appears i have more to pearn about boring. I always thought it gave more power, the cylinder is in great condition but the piston has some movement in it which is giving me a slight piston slap. Will look into the vforce reeds. So i dont need to change the jets just do a plug chop? Any other bits which are worth doing while its all apart? Different filter? Tors removal?
There are lots of different pistons, cast or forged, brand names etc. They require a certain amount of piston to cylinder clearance between forged or cast. You could have a crank rod with a bit of play helping you hear piston slap. Also blaster motors tend to be noisy in the lower end. You may or may not not be hearing piston slap. You could always remove the tors with no issues. An air filter is your choice but it never hurts to put a fresh oiled filter on and keeping up with the maintenance. I would also recommend blocking off and removing the oil injection and pre mix your fuel. Some like to run it alot of people do not like to run it. Your choice.
Here is a write up on doing a plug chop. http://www.blasterforum.com/threads/how-to-plug-chop.53237/
There is tons of jetting info under the carburetor section.
Here is a write up on doing a plug chop. http://www.blasterforum.com/threads/how-to-plug-chop.53237/
There is tons of jetting info under the carburetor section.
Thanks. Have taken the cyli der head off, the rod is fine without any play, goingnto be taking it to a 2 stroke place to have the work done. Will look into the tors removal but is it possible to put an idle screw on the carb? have thought about removing the oil tank just seems quite handy how i dont have to refil it every time i fill up, plus as its road legal i would have to carry a bottle around to. What benefits are there to removing it. Thanks
Make sure you get some references on the shop. They may be great at working on things but it takes a good machinist with the right equipment to do your jug the right way. Plug chop will tell you what you need to do on jetting. Reeds and a bore won't make much difference though. Changes to intake or exhaust or changing from injection to premix will change jetting. Many are solid against the stock oil injection, but also many are for it. I think it kinda depends at how good you are at maintenance and remembering to put oil in lol. As long is you keep some in it and bleed it properly anytime there was a chance of air getting in(low oil or flipping), it will prob be fine. You can get a tors eliminator kit that comes with what you need, including bit, tap, and idle screw. Just make sure the kit you get has all of it, some don't
I found this in the link below, explains it perfectly, LOL
Plug Chop Poetry
“Plug Chop, Plug Chop, Plug Chop” I cry!
“Until you learn to feel me,
You’ll have to do it by eye.”
When it's dirty and black, it's got the sh*ts,
You have too much gas you are running rich.
When its hot and white, but looks pretty clean,
You're 'bout to blow your sh*t up, you're running lean.
Poetry by Harold
http://www.mopedarmy.com/wiki/Plug_chop
more plug chops explained:
http://www.braigasen.com/howtoread.htm
http://www.kawtriple.com/mraxl/carb/plugchop.htm
http://www.rays-shop.com/2010/01/ho...they-are-telling-you-whats-going-on-in-there/
yes, the chop tells you the state of your air/fuel ratio at full throttle,
if the "smoke ring" is darker than cardbourd, you're rich,
go down a jet size, doing a chop for each size until it's nice cardboard brown. (slightly darker is OK)
the opposite for lean, too light of a "smoke ring" = go up on main jet until chop shows the correct color ring
On oil injection.
Unless you need to run an oil which will not inject, or want to change your oil/fuel ratio, keep using the injection system.
If you are forgetful, continually flipping the bike, or are a dirty operator, then pre mix.
The oil injection system is perfectly reliable if you look after it.
On a technical note changing from the stock injection ratio (approx 20:1) to what most folks run (32:1), you will loose a little bit of power.
Unless you need to run an oil which will not inject, or want to change your oil/fuel ratio, keep using the injection system.
If you are forgetful, continually flipping the bike, or are a dirty operator, then pre mix.
The oil injection system is perfectly reliable if you look after it.
On a technical note changing from the stock injection ratio (approx 20:1) to what most folks run (32:1), you will loose a little bit of power.
you better consult with all the big manufactuers, who's performance dirt machines are all premix @ 32/40:1
and the amsoil engineers who formulate 50/100:1 premix oils
as they'll be very surprised to learn they're missing out on power by skipping 20:1 oil injection systems.
the blaster injection system was included on this machine for ease of use by newbie riders, who this machine was targeted for, and the abuse they could throw at it in a wide variety of elevations and temps, and stay safely oiled in all of those.
nothing more, nothing less.
if more power was on their mind, they'd have skipped the restrictive pipe, modest port layout, poorly designed head, and the host of other performance restrictions used to keep power down.
I am not getting into a heated debate.
Lowering the amount of oil that is available to bathe the rings to aid sealing, will lower compression.
Reducing film strength will too, lower compression.
Lowering the amount of oil that is available to bathe the rings to aid sealing, will lower compression.
Reducing film strength will too, lower compression.
