engine flush or not ?

[jackinacabin]

Well the question is should i use a flush to really get the last nuggins out of my old 1989 high mileage 60000 ish miles gs 500 .. running ok , in fact very well considering slightly low compressiom   and due a change pretty soon ...want to get her as good as i can for the summer ... also advice wanted on the oil viscosity as the engine is somewhat worn and useds some ( not a huge amount ) of oil ... currently standard grade ... I have changed the oil  and filter a lot because she came to me as an abused oild bike and i want to keep her going as long as forever until the oneday rebuild  but hear stories that a flush can cause issues with older engines ... thanks folks 

[grader]

there is no need to run an engine flush if you have been doing regular oil and filter changes. if you are running 15-40 deisel oil and it is using oil, jump up to a 50 grade.

[jackinacabin]

Thanks , yes I am fastidiuos about oil changes , ok - i will jump a grade and see how that goes , just tiopped up and it looked pretty clean and very slippery so all good . Thanks for the reply ... I have been using the bike oil thus far and have a large tub  but when thats used I will  switch to a higher grade as you suggest

[Bluesmudge]

I don't even know what an engine flush is.
Just put new oil and filter in every 3,000 miles until you reach 100,000 miles and then replace the motorcycle.

[jackinacabin]

Well I will be delighted if it makes it to 100k ,,, still going well enough at more or less 60k but i think some of the horses may have turned into enthusiastic ponies ... love the old gs all the same ... probably get a good used engine in the  very long run or rebuild , whatever works out cheaper