getting slower

2 of my town mates are suffering from the same problem there getting slower over the past year ive noticed there speed has dropped ,one will only do 45 the other 50 down hill were as two years ogo the 50 mile a hour one would go off the clock down hill and 55 on the flat,cant see why it has hit both bikes ,they are kept in a shed so they dont get wet ive got 7 bikes that are road legal so they dont get used every day ,they may only go out once amonth,my 2 cubs dont suffer the same they go as fast as they all ways did,any ideas

Strange that, might be an air filter problem cubs are paper and Ts are foam dunno witch craft

I greased the front forks, greased the final drive, changed the air filter and changed the oil to castrol 4t oil £9.99 halfords and after that the bike was more responsive and gained 5 mph top end. I now get 60 mph down a long hill.

The other thing I noticed is different make fuel seems to give different top speeds. I tested this by letting the tank almost run out then filling it and then made a mental not of the top speeds on the same roads when there was no wind. Strange this is that my t80 is faster using tesco 95 unleaded.

The other thing to consider is that outside temp will effect performance as it is only 80cc and 45-55 mph isnt too bad. Also it will do 30mph two up riding up a very long steep hill, before the service that would have been 20-25mph. So a good service and the best oil is the best way to get the most out of it

stevepb wrote: I now get 60 mph down a long hill.

I would certainly not recomend doing this too often (if at all) otherwise you will end up blowing the engine up. The engine will last indefinitely if you keep it to 45mph.

I understand what you mean John, but I have covered 900 miles since I bought the bike and have only gone over 50 mph a few times. it's hard not to hit high revs though when i'm on my 9 miles ride to work, steep hills etc. However, i keep the revs down until I have covered a few miles and have warmed the engine. Most of my riding is done between 30 and 40 mph due to traffic.