Hi Everyone, Thought I would drop onto the intro page to say hello. I have owned a R Reg 900SS for about 17 years now, it has always been through the Main dealer network for the belts and a local garage for most of the other work. Having spent the last 8 years working on 2 stroke classic trials bikes I've decided to bite the bullet now I had hit 50 and do some of the work on her myself. A rough running after bringing her out of winter storage indicates a similar problem to I had 3 years ago where the injectors were clogged up so Ive started the strip down. Strangely when I was sold the bite I was told by the previous owner (a local dealership) that whilst it was the facelift model it was actually the last of the carb only engines so I was pleasantly surprised when I started pulling it apart to find a pair of injectors! And so begins the fun. Trying to find IW 031's leads me most of the time to £40 ones from China via Ebay. Im struggling to find good UK based replacements so a possible full check and refub service might be the order of the day. Anyway, hopefully you should see me on the forum a bit more as I start to enjoy working on the bike whilst lockdown continues...
Welcome to the twilight zone. I've got a red 2001 model just on the verge of 50,000 miles, what's yours? They are very easy to service etc yourself, have fun with the spanners!!!!
Welcome to the Forum Robert Before you go stripping her apart have you used fresh fuel and a proprietary injector cleaner (for petrol) like Redex? Sometimes it can be as simple as that.
Hi Paul, Unfortunately I went straight down the "tear down" route. She had a few other things that needed doing like some stress cracks on the lower fairing mounting etc so I threw caution to the wind! I sort of thought hmmmm when it said Step 1 - remove seat, Step 2 remove lower (OK a few stuck bolts here but a good chance to replace them with new ones and it had to come off anyway) Step 3 remove tank (OK getting a bit more complex, a few new pipes to contend with) then Step 4 ... remove airbox... I mean how difficult can it be ?? Its one hose clamp and a bolt on my Bultaco... yep 2 hrs later! found the front retaining bolts after dropping the oil cooler etc then worked my way around the 3 miles of wiring loom! Back to original question though, it was a fresh tank of fuel, she started and ran OK with a small residue of fuel in the tank then when I got to the petrol station and filled her up, the rough running started. Basically low power, one cylinder hunting and cutting in and out, if you increased revs very slowly you just got a lower power delivery but smooth, if you cracked it on fast if just hunted and came in and out. I ruled out a possible fuel filter as that would probably have the symptom more exteeme and I had the same issue 3 years ago which was sorted by a garage with a fue system strip down. Hindsight being a lovely think, a additive may have sorted it by as we are in lockdown still in North Wales there is no opportunity to ride so I thought I may as well take her apart, give her a really good check over and learn a bit about the bike... The challenge now is trying to source a new set of injectors. Ive got 3 options, send mine off for a service, buy the ones on ebay for £40 but they come from China and I wonder just how good they would be (I suspect not good?) or try and source some UK ones but they just seem to be refurbed ones with a mark up on them?
Hi Wayne, just under 19,000 miles. She has not had a lot of use due to my work pattern but I am looking forward to putting more miles on her over the next few years. Most of my riding has been off road on classic trials bikes (1980's Bultacos and Yamaha Majesty's)
You look after it and it will look after you. In my opinion one of the best bikes you can buy at very little cost and bags of fun fun fun!!!!!
Two things I can suggest. 1. Are you sure the fuel hoses in the tank haven't deteriorated through being immersed in ethanol fuel. Could be low fuel pressure. 2. I clean my injectors by putting them on a 9v battery to open them. Clean with brake cleaner and a airline. It works for me. Hope you get it sorted.
Thanks Akorenika, I was wondering if there was a home method of doing a basic check of the injectors. Some one else also advised me to set up a basic fuel line from the tank, connect the injectors up to the loom, and turn it over to look at the spray pattern.... I assume the fact you stipulate 9v means that the injectors have a lower voltage to trigger? I have a 12v lighting set up in the garage so have a 12v to hand but try and get a 9v if needed to do the home test
9 v is enough to open them but not damage them. I used a 9v block battery because I had one handy. When they open you might see some deposit that has built up over time. I had similar symptoms a few years back and the in-tank fuel lines had gone to jelly and perrished. Dropped the fuel pressure just enough so it would still start but not run right.
Totally agree, fell in love with it at the bike show and promised myself I would have one, one day...
@Robert Sloggett spending when it was last done (and you should know having had the bike 17 years) it might be worth replacing the fuel filter as well while the tank is off and you've opened it up to check those fuel lines.
Replaced my fuel filter not long after getting it (5 years ago) was having issues, took it out, dated 2001, it had not been changed since birth, the tank was full of crap so flushed it all out and cleaned the bottom filter( mesh thing ) and what an improvement with performance!!!!
Yep, I had an intermittant misfire on my 748 around 9-10k rpm, lots of suggestions pointed at the crank sensor but that was all OK, after I serviced the bike myself fully for the very first time back in 2018, it having been done at dealers before then, I replaced the fuel filter. The one in the tank was dated 2003. When the new one went in the misfire went - magic
