new29er

Hi guys, I'm new to this site and up until four months ago I hadn't cycled for twenty+ years. I'm loving it so I decided to invest a bit more money. I have just bought some Rockshox Reba off ebay. They were New(other). They have 120mm of travel and according to the guy I bought them off they are 2017. I want to change the travel to 100mm so I've bought the 100mm air shaft to convert it. I read the 2017 service guide rev B and watched a number of vids on how to do the swap over and I was feeling quite confident until I read the 2017-2019 service guide and I noticed that on the 100mm shaft there is a jounce bottom out bumper. It is highlighted at the top of page 17 as though either the others don't have one or the 100mm one is different to the others in some way. I have looked at just about every service kit and parts list you can think of and I can't find one??? If it is just on the 100mm air damper shaft then me converting to a 100mm without one could damage the forks.

If all the newer models have them no matter what travel they are then I might be able to use the one off the other air shaft but if it is just the 100mm that has it then I could be putting the forks at risk putting them together without one. It's on the outer part of the retaining ring right at the end of the shaft.

If it's any help the forks are the Reba boosted 120mm travel with the tapered steerer and it is the crown lockout. The serial number is 18T73493080. I read somewhere that the 18 is the week it was made and I've also read that they change the year of the forks around May or June and if my information and maths are correct then mine were made the first week of May so I can't even tell you the exact year.

I basically want to know if I can just take the components off the 120mm air shaft and put them on the 100mm and it will be fine or if it will damage them. I don't even know if the 120mm shaft has a bumper of it's own and it is ok to use that. Sorry for the really long thread.

Any help you can give me will greatly appreciated.

fietsbob

Just Buy the fork with the features you now want.

new29er

£470 doesn't come easy to me. I bought the forks because they were new and cheap, even with the air shaft damper cost. I'd been watching vids on forks and it looked like a simple task to change over the air shaft and I have the tools to do it so I figured why not.

70sSanO

I'm sure there are people here who can answer your question, but you may also want to ask it on MTBR.

John

jimc101

Go to a good LBS who can service RS forks, as they will know what they are doing, alternatively, somewhere like TF Tuned, as you appear to be out of your depth with this project.

new29er

I wouldn't say I was out of my depth. I was looking for someone who had stripped Reba's 2017-2018 forks to do a lower leg service. I was hoping they could tell me if they had a rebound bumper in their forks or if it was something Rockshox had decided not to use after all. The reason why I have the tools to do these jobs is because I used to fix motorbikes and I wouldn't dream of leaving a part out of a bike just because it was difficult to find. I know my post was a bit long and it seemed like I was in a panic but I had spent all day looking for a part that might not exist and I didn't want to strip the forks to find out if it had an extra damper at the end of the shaft. I wouldn't be able to sell them on as new (other) if I did that. I appreciate your advice though guys. I will let you know how I got on.

hyhuu

Your terminology is all over the place. I'm assuming you are talking about just the air shaft. I've yet to see an air fork, regardless of brand, without a top out bumper. It's just a piece of rubber. Unless it doesn't fit, I don't see how it wouldn't work. Within the same brand, many parts are interchangeable. You can go to mtbr forum and ask. There are people there who replaced the bumper with something else softer that they found at homedepot.

new29er

Hyhuu. Please look at the SRAM website and at the 2017-2019 Reba service manual and you will see what I mean. I have never seen an extra damper after the retaining ring at the end of the shaft. I have watched about 5 different youtube videos on the lower leg service and never seen one at the end of the shaft in any of them. I have read all of the 2017 Reba service manual (rev B) and it is not in that one either. It is only in the 2017-2019 manual, page 17 and then it is mentioned again further in the manual. I know that behind the retaining ring there is a damper but this is at the end of the shaft. If I'm still wrong somehow I will hold my hands up to it.

jimc101

Linky needed, still thinking you'd be best off going to a pro for this

fietsbob

You have met the economy of scale , a Manufacturer orders a thousand, at an each price, much lower than a retail consumer, wanting just 1.