Gday all, I am going to post this thread and update with progress shots as I clean up my GSX 250.. When I picked this bike up it wasn't starting, hadn't been ridden in a year or so, was filthy, indicators didn't work, tacos were hanging off the handlebars though all in all wasn't in too bad a shape mechanically. Things I've done to date: -Got it running well; -Changed out the indicators; -Cleaned and polished; - Fixed the exhaust which had a few holes along the bottom. Things I want to do: - get the seat reupholstered - Clean up the front end of the bike including forks, handlebars, headlamp; - new tachos; - restore the spoked rims (spokes very rusted) - new rear light Photos attached! Feel free to make suggestions for my bike or equipment recommendations! Marcus
Thanks, yeah it runs quite well actually. The pods needs to be replaced as the rubber seals are a little cracked and wires a bit pitted and fabric clogged. The bike tops out at 100kms an hour on a flat road. I'd have no idea if that's the norm for a 1983ish gsx250... though it sounds great when I'm just putting around town. I've just changed out the oil (first time since I bought it)... and the filter and oil is horrendous... should run a bit better with the new oil.
Sorry dude but thats garbage, ive had mine to 150 on a long flat road, i found it really hard to get it to run right on pods so i cut my airbox in half and went up a main jet size , with a more open muffler it goes well. Otherwise ,sweet looking bike i love the straight bar and the polished side cases
The Gearing Commander website has the 79-85 GSX250 listed with a top speed of 149 km/h in 6th gear @10,000 rpm with standard gearing (14T front / 46T rear sprocket's, 110/90/18 rear tyre)
Nice bike. The slow top speed may be to do with the dumb pods not letting enough air through. You can see on the above picture how they have been sucked in, making the sides curved. They have probably ruined the jetting too. Have you checked the plugs to see if it is running lean/rich? To work out what you need try this. Using 250cc @10,000rpm and volume efficency of .8 = 43 cubic feet of air per minute. Then use this to find size of air cleaner. http://www.gnttype.org/techarea/turbo/airfilter.html Using this formula the pod should be 3" dia x 10" long (75x250mm). http://2fiftycc.com/index.php?threads/suzuki-gsx-250.9148/#post-95665. And another one. http://www.secondstrike.com/Technical/AirCleanerCalc.asp
So Using these calculations the paper air filter sitting in the airbox of my VT250 will give a pressure drop of 0.01% at 14,000 rpm. Think that will do me.
@MarcusG, Murdo is on the money. If you want to confirm what he's saying, find a bit of road; remove the pod filters; go for a high speed run. I'm guessing you'll get to 130 even if the jetting isn't right. Put the filters back on, go home and maybe see if you can go to a modified airbox scenario like the one @Alipture mentioned.
Thanks gents, it's good to get some feedback on how this bike should run. I've set the carby to factory settings and can still only get up to 100 with the pods. Though I might try out a run without the pods on just to see how it goes. Just changed the oil and filter for the first time since buying over the week end and it was absolutely filthy.. very gluggy stuff.
Thanks heaps murdo, I will work through this and post back to this thread with the results! I've only got a very basic understanding of carbys so any help is appreciated. I have checked the plugs a number of times after rides and they run rich with the mixture screws set to factory settings..
Yea theres stuff there for the GSX also that u will be able to access http://2fiftycc.com/index.php?resources/categories/gs250-gsx250.34/
Thanks. I don't know why the air box was taken off this bike if it only worsens the performance. I'll try fix this up over coming weeks.
Yeah, it would be a good idea (a good starting point) trying to get it as close to the factory specs as you can. On the other hand, your bike's frame seems to have all the various "unnecessary" tabs removed, if I'm not mistaken, and thus you'd have to think something out, how to secure the airbox in place ('cause it has three screws on both side, if my memory serves correct). If a proper airbox setting would be too hard/expensive to recreate, then an other option would be to get some decent foam filters of the appropriate size (diameter), y'know the ones, they look like pods, but instead of a metal cone there is foam. These seem to get a much better rep than the metal pods.
Its the usual path to take with the GSX .... 'pods' and open/ cone exhaust .... I have the same setup ready for mine as obviously its done for a more appealing look with all the other changes. But of course mostly everyone has the same performance problems ..... I think it needs to be running nicely on the stock setup before the changes begin .... then a step by step tweak Heres a good read of Bens challenges he faced .... he even borrowed my original airbox to try and sort it out . An epic saga .... http://2fiftycc.com/index.php?threads/bens-gsx250-cafe-project.1737/ The stock airbox creates the correct airflow , not just to hold the filter .... and the stock exhaust creates the correct back pressure , not just to control the noise released from the motor. If I ever get to my GSX then Im going to try something like this .... to create a bit of 'travel' for the incoming air