I just bought a 88' trx250r. The quad has alot of aftermarket stuff on it. I don't know anything about the internal engine parts(bore,stroke,etc.)but it does have a curtis sparks exhaust,works triple rate onfront,pep on rear,extendedaxlewith itp baja wheels,rpm shrouds,and so on.My questions start with spark plugs,it's got ngk b8es in it,does this seem right?Next, the swingarm looks aftermarket but i can't find any i.d. on it.It is very nicely done in black and frrom what i can tell looks alot like a lsr but i cant find a good picture of a lsr to see.Now fuel,what ratio,and what oil,synthetic or castor. i'm running 32:1 with hr1(91 octane) bike had race gas in it when i got it and i will get some phillips 66 101 octane this weekend.Any info would be appreciated. Also if any might know this bike it has new maier silver plastic along with the above mentioned,also has a "WEST TENN CHOPPER" iron cross decal on hood. supposedly was a trade in on a new quad.THANKS

 

the only help i can offer to you is that if it had race gas in it when you got it that means that the head was honed or shaved to increase compression which would require race gas. and if so that means that a shorter spark plug must be used. sorry i can't offer any help about the swingarm.

 

1- even if the head was shaved you still should use a BR8ES plug. gaped at .22. 2- Its an 88 so if the swing arm was stock it would have 4 screws in it for the chain adjuster to work. (located right at the end or the swing arm) Most aftermarket swing arms only have two. 3- 32:1 is an ok ratio. ts a little bit rich thow. if your going to keep runnin synthetic oil then go to 40:1. It will run cleaner and have more responce.

 

thanks guys.the swingarm has only 2 bolts (1 on each side) that seem to clamp around bearing carrier, are these the ones you are talking about?Im using a b8es ngk plug ,no "r" in the #.Bike seems pretty fast and quick, but always looking 4 the little things. THANKS AGAIN

 

One more ? What is the stock width of the frontend. I cant decide if the a-arms are extended or not.

 

.....Then yes that is probably an aftermarket swing arm then. The stock width acorrding to honda was right around 45.7" give or take one or two. It should be right near there somewhere. The "R" in BR8ES stands for "resistor type spark plug". The stock electrical system is a resistor type on the 250R. It porbably wont hurt nothing but just to let you know man.

 

..try here might help you better www.rriders.com

 

i got a stock 88 250R and i have a ngk b8es plug in mine and for fuel i run a 20:1 ratio. ( thats what it says on my gas tank)

 

An NGK B8ES is fine or you can use the resistor version, makes no difference. You could have an '86 or '87 stock swingarm, the '88 - '89 stock swing arms were aluminum, the '86 - '87 were steel and painted a gold color and the first two years they only had 2 bolts to tighten the bearing carrier, the '88 - '89 swing arm has 4.

You will get a hundred different opinions on oil and oil fuel ratio. I personally run Amsoil at 32:1 and have great success with that. I also run 110 octane with a high compression dome in an ESR 310 kit. If the bike was running race gas there was a reason for that so unless you want to experience some serious detonation by not running a high enough octane I'd continue using race gas.

 

or you could just check the compression and see if you really do need race gas or not..