grisley bikes belonged to BH bikes from Vitoria, Spain a traditional bike manufacturer here (not high spec or custom bikes, just that they were building the bikes that everybody was riding for generations here... road, "bmx", cruisers, mtb... you name it and there was a bh there)
During the mid 90s they hired Peter Grisley from USA, who was supposed to design the frames and put his name on them, and the flag too...but the brand behind was BH. I think they did this for marketing reasons.
At some point not after their foundation they tried to sell Grisley bikes in USA and several other countries apart from Spain (that was their main market) in Europe, so yours belong to that era... i lost track of the brand but it was discontinued as the mega tubes altough shocking and spectacular did not provide a good compromise between rigidity and weight.... they did not use light butted alu so they were pretty rigid but not light at all. It was just that alu was popular when compared to Chromoly for the mass market by then and its look with those big tubes helped the sales
They were popular here in Spain for a few years but obviously not looked as a premium brand, just solid mid range bikes for the mass market.
I think that during 1995 they had the best two national riders on their bikes (Manuel Martinez Costa & Juan Carlos Garro) that had a good season on them
As i say you will not break the bike, they are solid!
If you want more info check the net for it, just look for "bicicletas grisley BH" or something like that, or get registered in www.bicisclasicas.com
and post a question about it (do in in English no worries)