Hi guys, I'm hoax, 21 and from sheffield. I'm a mechanic by trader, but fettle with my two other bikes when i can. I own a 2002 zxr400 L9 and a 1997 zx7r P2 which are both currently off the road . Last year i gave my zxr400 a closer look at the scenery out in penistone and while i was rebuilding i needed a run around. My dad was given a 1996/97 sr50 for nothing as a none runner/shitter, we came to the agreement that if i paid for the parts to get it running i could have it. Bonus. £50 later and shes a minter, cough running turd. Anyway i've used it over the last year and it's starting to show afew signs of dying :'(, it seems down on power but not by alot. The main problem is when i come to a hill or have to slow down and then accelerate again it just wont pull, and end's up with me having to pull over and set off again. Last week i changed the plug, cleaned the sponge air filter out and cleaned the carb out. It seemed better that day, but was the same again the next day. Checked the compression today and was 140psi cold, so that seems alright. Any suggestions guys? Hoax
If it is the same tank of fuel that was in it last year, drain it out and put some fresh unleaded in. Next you should check your rollers and belt because lord knows when they were replaced.
Thanks for the reply. I've used it pretty much 6 days aweek for the last year, so a fresh tank of fuel everyweek. I noticed when i stripped the carb that it doesnt have a filter, so going to purchase a small inline fuel filter and some gearoil, as its never been changed under my ownership. Hoax
Filter and gear oil change would be good but I would replace the rollers as I guarantee if you been using it for a year they will be knackered now. To check the rollers for wear look for flat spots. Thats where my money would go first. Is the bike standard?
I'm 90% sure the entire bike is standard. How easy are they to get at and looking on a couple of sites they show various weights. where should i start? Hoax
The first thing that is usually modified is the exhaust so if that is standard its likely that it is fully standard. You need to take the bolts off the transmission casing then you will need a variator locking tool with a torque wrench or an impact wrench with some care! I'm not sure what weight is standard. I would imagine somewhere around 6g. They may be marked on the rollers.
Update Bought gearoil, inline filter and rollers. Found out from my local motorcycle shop that it has 5.5g as standard, and that he had 5.5, 5.0 and 4.5 in stock. I went for the 5.0, but he couldnt find them in stock so went for the 4.5. Do you think it'll be alright/good choice? Need to sort it asap, as its really struggling now. Will be fitting tomorrow when i'm at work so i can use my air gun.
it might be slightly light so you may slightly lose top end. If the bike revs silly high and with little speed you will need to go back to 5.5. I had 2.9g in my 50cc and it sounded like it would blow up it was ridiculous. Run the 4.5s it shouldnt be that bad but expect to lose top speed
if the bikes standard then use standard weight rollers they arent hard to change if youve got an impact gun just whip the nut off and remove the variator, youll probably find flat spots on the rollers or they could be cracked, just take them out and put the new 1s in and put it back together
Okay i'll go for the standard 5.5g rollers. I just thought from what i read that finding the correct weight rollers would optimise when it changed up.
Yes that is correct in a tuned bike if it was tuned and you weren't sure what rollers were in the bike you should buy a set to find the optimum peak power. As Nathan says if it is standard go for 5.5, I don't believe you should notice much of a difference with a 0.5 or 1 gram. Maybe try the 4.5s and see but if it is too revvy the engine components will wear out quicker so avoid prolonged use.
